Substrate processing apparatus

ABSTRACT

A drive system for a transport apparatus includes a plurality of permanent magnets connected to the transport apparatus, a plurality of stationary windings exposed to a field of at least one of the plurality of permanent magnets, a control system for energizing the stationary windings to provide magnetic force on the transport apparatus, and an arrangement of ferromagnetic components proximate at least one side of the transport apparatus for providing passive stabilization of lift, pitch, and roll of the transport apparatus.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of co-pending U.S.application Ser. No. 10/624,987, filed Jul. 22, 2003, which claims thebenefit of U.S. Provisional Application No. 60/397,895, filed Jul. 22,2002, both of which are incorporated by reference in their entirety.

BACKGROUND

The embodiments and methods described herein relate to substrateprocessing apparatus and, more particularly, to substrate processingapparatus with chambers interconnected in a Cartesian arrangement.

One of the factors affecting consumer desire for new electronic devicesnaturally is the price of the device. Conversely, if the cost, and hencethe price of new electronic devices can be lowered, it would appear thata beneficial effect would be achieved in consumer desires for newelectronic devices. A significant portion of the manufacturing costs forelectronic devices is the cost of producing the electronics which startswith the manufacturing and processing of semi-conductor substrates suchas used in manufacturing electronic components, or panels used formaking displays. The cost of processing substrates is affected in partby the cost of the processing apparatus, the cost of the facilities inwhich the processing apparatus are housed, and in large part by thethroughput of the processing apparatus (which has significant impact onunit price). As can be immediately realized, the size of the processingapparatus itself impacts all of the aforementioned factors. However, itappears that conventional processing apparatus have reached a dead endwith respect to size reduction. Moreover, conventional processingapparatus appear to have reached a limit with respect to increasingthroughput per unit. For example, conventional processing apparatus mayuse a radial processing module arrangement. A schematic plan view of aconventional substrate processing apparatus is shown in FIG. 1. As canbeen seen, the processing modules of the apparatus in FIG. 1 are placedradially around the transport chamber of the processing apparatus. Thetransport apparatus, which is a conventional two or three axis ofmovement apparatus (e.g. Z, θ, T Axis) is centrally located in thetransport chamber to transport substrates between processing modules. Ascan be realized from FIG. 1, throughput of the conventional processingapparatus is limited by the handling rate of the transport apparatus. Inother words, throughput cannot be increased with the conventionalapparatus by merely adding processing modules to the apparatus, becauseonce the transport apparatus reaches a handling rate peak, this becomesthe controlling factor for throughput. The structure and techniques ofthe disclosed embodiments overcome the problems of the prior art as willbe described further below.

SUMMARY OF THE DISCLOSED EMBODIMENTS

In accordance with one embodiment, a drive system for a transportapparatus includes a plurality of permanent magnets connected to thetransport apparatus, a plurality of stationary windings exposed to afield of at least one of the plurality of permanent magnets, a controlsystem for energizing the stationary windings to provide magnetic forceon the transport apparatus, and an arrangement of ferromagneticcomponents proximate at least one side of the transport apparatus forproviding passive stabilization of lift, pitch, and roll of thetransport apparatus.

In accordance with another embodiment, a processing apparatus includes atransport chamber, at least one processing module communicativelycoupled to the transport chamber, a transport apparatus for transportinga workpiece between the transport chamber and the processing module, anda drive system for providing magnetic force for moving the transportapparatus through the transport chamber. The drive system includes aplurality of permanent magnets connected to the transport apparatus, aplurality of stationary windings exposed to a field of at least one ofthe plurality of permanent magnets, a control system for energizing thestationary windings to provide magnetic force on the transportapparatus, and an arrangement of ferromagnetic components proximate atleast one side of the transport apparatus for providing passivestabilization of lift, pitch, and roll of the transport apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the presently disclosedembodiments are explained in the following description, taken inconnection with the accompanying drawings, wherein:

FIG. 1 is a schematic plan view of a substrate processing apparatus inaccordance with the prior art;

FIG. 2 is a schematic plan view of a substrate processing apparatus inaccordance with a first embodiment;

FIG. 3 is a schematic plan view of a substrate processing apparatus inaccordance with another embodiment;

FIGS. 4-5 are respectively schematic plan views of substrate processingapparatus in accordance with still other embodiments;

FIG. 6 is a schematic plan view of a substrate processing apparatus inaccordance with yet another embodiment;

FIG. 7 is a schematic plan view of a substrate processing system withtwo substrate processing apparatus in accordance with anotherembodiment, and FIG. 7A is another schematic plan view of the substrateprocessing system in accordance with yet another embodiment;

FIG. 8 is a schematic plan view of another conventional substrateprocessing apparatus;

FIG. 9 is a schematic plan view of a conventional substrate processingsystem including a number of conventional processing apparatus and astocker;

FIG. 10 is an end view of a platen drive system of the substrateprocessing apparatus;

FIGS. 11A-11B are respectively an end view, and a section view (takenalong lines 11B-11B in FIG. 11A) of another platen drive system of thesubstrate processing apparatus;

FIG. 12 is a top view of an exemplary cart of the substrate processingapparatus in accordance with another embodiment of the apparatus;

FIG. 12A is another top view of the exemplary cart in FIG. 12 with thecart shown in an extended position;

FIG. 12B is an end view of the exemplary cart in FIG. 12 in a portion ofa chamber of the apparatus;

FIG. 13A is a top end view of a portion of a chamber of the apparatuswith a drive system and transport cart in accordance with anotherembodiment of the apparatus;

FIG. 13B-13C respectively are a section view of the chamber and carttaken along lines 13B-13B in FIG. 13A, and another section view takenalong lines 13C-13C in FIG. 13B;

FIG. 13D is a schematic diagram of an exemplary drive system of theapparatus;

FIG. 14A is an end view of another embodiment of a cart used with theapparatus in FIG. 2;

FIG. 14B is a graph illustrating the relationship between axialdeflection Z and a restoring force F of the drive system;

FIGS. 15-16 are respectively a schematic perspective view and anexploded elevation view of semiconductor workpiece transport cart of theapparatus in accordance with another embodiment;

FIG. 17 is a schematic perspective view of the transport cart inaccordance with another embodiment;

FIG. 18 is a cross-section of a portion of the transport apparatus inFIG. 2 and a workpiece chuck rotation device of the apparatus;

FIGS. 19-20 respectively are elevation views of the workpiece chuckrotation device and a transport cart of the apparatus with the transportcart in different positions;

FIG. 21 is another schematic elevation of the chuck rotation device inaccordance with yet another embodiment;

FIGS. 22-23 respectively are a schematic top plan view and schematicelevation view of yet another embodiment of the transport cart for theapparatus;

FIGS. 23A-23B respectively are other top plan views of the transportcart in FIG. 22 with a transfer arm of the cart in two differentpositions;

FIG. 24 is a schematic elevation view of another embodiment of thetransport cart;

FIGS. 24A-24C respectively are plan views of the transport cart in FIG.24 with the transport arm linkage of the cart in three differentpositions;

FIG. 25 is a schematic elevation view of still another embodiment of thetransport cart;

FIGS. 25A-25C respectively are plan views of the transport cart in FIG.25 with the transport arm linkage of the cart in three differentpositions;

FIG. 26 is a schematic diagram of system control software in thecontroller of the apparatus;

FIG. 27 shows an exemplary embodiment of a drive system for a transportapparatus;

FIGS. 28A-28D show a drive system embodiment with propulsion windingsalong one side of the transport apparatus;

FIGS. 29A-29C show an exemplary embodiment of a drive system withpropulsion windings along two sides of the transport apparatus;

FIG. 30 shows an embodiment with a set of propulsion windings and a setof lift windings;

FIG. 31 shows another embodiment with a set of propulsion windings and aset of lift windings driven by a different amplifier configuration;

FIG. 32 shows another embodiment with a set of propulsion windings and aset of lift windings driven by yet another amplifier configuration;

FIG. 33 shows an exemplary embodiment utilizing two propulsion windingsets and three lift winding sets;

FIGS. 34A-34D show an exemplary embodiment with two propulsion windingsets and four lift winding sets;

FIGS. 35A, 35B, and 36 show exemplary embodiments with four propulsionwinding sets and four lift winding sets;

FIGS. 37 and 38 show exemplary embodiments with four propulsion windingsets and four lift winding sets driven by individual amplifier channels;

FIGS. 39A-39C show an arrangement of magnetic platens for providingdevice actuation on the transport apparatus;

FIG. 40 shows an exemplary embodiment including a pair of rotors;

FIG. 41 shows a grid of ferromagnetic rails for providing passive forceson the transport apparatus;

FIG. 42 shows another mechanism for providing passive forces on thetransport apparatus; and

FIGS. 43A-43C show various winding and magnet patterns that may be usedtogether.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring to FIG. 2, there is shown a schematic plan view of a substrateprocessing apparatus 10 incorporating features of the disclosedembodiments. Although the disclosed embodiments will be described withreference to the drawings, it should be understood that they may includemany alternate forms of embodiments. In addition, any suitable size,shape or type of elements or materials could be used.

The substrate processing apparatus 10 is connected to an environmentalfront end module (EFEM) 14 which has a number of load ports 12 as shownin FIG. 2. The load ports 12 are capable of supporting a number ofsubstrate storage canisters such as for example conventional FOUPcanisters; though any other suitable type ma be provided. The EFEM 14communicates with the processing apparatus through load locks 16 whichare connected to the processing apparatus as will be described furtherbelow. The EFEM 14 (which may be open to atmosphere) has a substratetransport apparatus (not shown) capable of transporting substrates fromload ports 12 to load locks 16. The EFEM 14 may further includesubstrate alignment capability, batch handling capability, substrate andcarrier identification capability or otherwise. In alternateembodiments, the load locks 16 may interface directly with the loadports 12 as in the case where the load locks have batch handlingcapability or in the case where the load locks have the ability totransfer wafers directly from the FOUP to the lock. Some examples ofsuch apparatus are disclosed in U.S. Pat. Nos. 6,071,059, 6,375,403,6,461,094, 5,588,789, 5,613,821, 5,607,276, 5,644,925, 5,954,472,6,120,229 and U.S. patent application Ser. No. 10/200,818 filed Jul. 22,2002 all of which are incorporated by reference herein in theirentirety. In alternate embodiments, other lock options may be provided.

Still referring to FIG. 2, the processing apparatus 10, which as notedbefore may be used for processing semiconductor substrates (e.g. 200/300mm wafers), panels for flat panel displays, or any other desired kind ofsubstrate, generally comprises transport chamber 18, processing modules20, and at least one substrate transport apparatus 22. The substratetransport apparatus 22 in the embodiment shown is integrated with thechamber 18. In this embodiment, processing modules are mounted on bothsides of the chamber. In other embodiments, processing modules may bemounted on one side of the chamber as shown for example in FIG. 4. Inthe embodiment shown in FIG. 2, processing modules 20 are mountedopposite each other in rows Y1, Y2 or vertical planes. In otheralternate embodiments, the processing modules may be staggered from eachother on the opposite sides of the transport chamber or stacked in avertical direction relative to each other. The transport apparatus 22has a cart 22C that is moved in the chamber to transport substratesbetween load locks 16 and the processing chambers 20. In the embodimentshown, only one cart 22C is provided, in alternate embodiments, morecarts may be provided. As seen in FIG. 2, the transport chamber 18(which is subjected to vacuum or an inert atmosphere or simply a cleanenvironment or a combination thereof in its interior) has aconfiguration, and employs a novel substrate transport apparatus 22 thatallows the processing modules to be mounted to the chamber 18 in a novelCartesian arrangement with modules arrayed in substantially parallelvertical planes or rows. This results in the processing apparatus 10having a more compact footprint than a comparable conventionalprocessing apparatus (i.e. a conventional processing apparatus with thesame number of processing modules) as is apparent from comparing FIGS. 1and 2. Moreover, the transport chamber 18 may be capable of beingprovided with any desired length to add any desired number of processingmodules, as will be described in greater detail below, in order toincrease throughput. The transport chamber may also be capable ofsupporting any desired number of transport apparatus therein andallowing the transport apparatus to reach any desired processing chamberon the transport chamber without interfering with each other. This ineffect decouples the throughput of the processing apparatus from thehandling capacity of the transport apparatus, and hence the processingapparatus throughput becomes processing limited rather than handlinglimited. Accordingly, throughput can be increased as desired by addingprocessing modules and corresponding handling capacity on the sameplatform.

Still referring to FIG. 2, the transport chamber 18 in this embodimenthas a general rectangular shape though in alternate embodiments thechamber may have any other suitable shape. The chamber 18 has a slendershape (i.e. length much longer than width) and defines a generallylinear transport path for the transport apparatus therein. The chamber18 has longitudinal side walls 18S. The side walls 18S have transportopenings or ports 18O formed therethrough. The transport ports 18O aresized large enough to allow substrates to pass through the ports (can bethrough valves) into and out of the transport chamber. As can be seen inFIG. 2, the processing modules 20 in this embodiment are mounted outsidethe side walls 18 s with each processing module being aligned with acorresponding transport port in the transport chamber. As can berealized, each processing module 20 may be sealed against the sides 18Sof the chamber 18 around the periphery of the corresponding transportaperture to maintain the vacuum in the transport chamber. Eachprocessing module may have a valve, controlled by any suitable means toclose the transport port when desired. The transport ports 18O may belocated in the same horizontal plane. Accordingly, the processingmodules on the chamber are also aligned in the same horizontal plane. Inalternate embodiments the transport ports may be disposed in differenthorizontal planes. As seen in FIG. 2, in this embodiment, the load locks16 are mounted to the chamber sides 18S at the two front most transportports 18O. This allows the load locks to be adjacent the EFEM 14 at thefront of the processing apparatus. In alternate embodiments, the loadlocks may be located at any other transport ports on the transportchamber such as shown for example in FIG. 4. The hexahedron shape of thetransport chamber allows the length of the chamber to be selected asdesired in order to mount as many rows of processing modules as desired(for example see FIGS. 3, 5, 6-7A showing other embodiments in which thetransport chamber length is such to accommodate any number of processingmodules).

As noted before, the transport chamber 18 in the embodiment shown inFIG. 2 has one substrate transport apparatus 22 having a single cart22C. The transport apparatus 22 is integrated with the chamber totranslate cart 22C back and forth in the chamber between front 18F andback 18B. The transport apparatus 22 has cart 22C having end effectorsfor holding one or more substrates. The cart 22C of transport apparatus22 also has an articulated arm or movable transfer mechanism 22A forextending and retracting the end effectors in order to pick or releasesubstrates in the processing modules or load locks. To pick or releasesubstrates from the processing modules/load ports, the transportapparatus 22 may be aligned with desired module/port and the arm isextended/retracted through the corresponding port 18O to position theend effector inside the module/port for the substrate pick/release.

The transport apparatus 22, shown in FIG. 2 is a representativetransport apparatus and, includes a cart 22C which is supported fromlinear support/drive rails. The transport apparatus will be described ingreater detail below. The linear support/drive rails may be mounted tothe side walls 18S, floor, or top of the transport chamber and mayextend the length of the chamber. This allows the cart 22C, and hence,the apparatus to traverse the length of the chamber. The cart has aframe, which supports the arm. The frame also supports caster mounts orplatens 22B, which move with or relative to the frame. As will also bedescribed further below, a sequential synchronous linear motor 30 drivesthe platens 22B and hence the cart 22C along the rails. The linear motor30 may be located in the floor or side walls 18S of the transportchamber. A barrier, as will be seen further below, may be locatedbetween the windings of the motor and the motive portion of the platensto isolate the windings from the interior of the chamber. In general,the linear motor may include a number of drive zones. The drive zonesare located at locations along the transport chamber where the arm 22Ais extended/retracted (i.e. at the rows YO-Y2 in this embodiment ofmodules/ports). The number and density of drive zones is dependent onthe number of platens per cart, the number of motors per chamber, thenumber of process modules or exchange points etc. In this embodiment,the arm is operably connected to the platens 22B by a suitablelinkage/transmission so that when the platens are moved by a drive motorin relative motion to each other the arm is extended or retracted. Forinstance, the transmission may be arranged so that when the platens aremoved apart along the rails the arm is extended to the left, and whenmoved back closer together the arm is retracted from the left. Theplatens may also be suitably operated by a linear motor toextend/retract the arm 22A to/from the right. The control of movement ofthe platens over the slide rails with the linear motor, as well asposition sensing of the platens and hence of the cart and theextended/retracted position of the arm may be accomplished in accordancewith international application having publication numbers WO 99/23504;99/33691; 01/02211; 01/38124; and 01/71684, which are incorporated byreference herein in their entireties. As can be realized, the platensmay be driven in unison in one direction in order to move the entirecart/apparatus in that longitudinal direction inside the transportchamber.

FIG. 3 shows another embodiment of a substrate processing apparatus 10′which is generally similar to apparatus 10. In this embodiment, thetransport chamber 18′ has two transport apparatus 122A, 122B. Thetransport apparatus 122A, 122B are substantially the same as theapparatus 22 in the previously described embodiment. Both transportapparatus 122A, 122B may be supported from a common set of longitudinalslide rails as described before. The platens of the cart correspondingto each apparatus may be driven by the same linear motor drive. Thedifferent drive zones of the linear motor allow the independent drivingof individual platens on each cart and thus also the independent drivingof each individual cart 122A, 122B. Thus, as can be realized the arm ofeach apparatus can be independently extended/retracted using the linearmotor in a manner similar to that described before. However, in thiscase the substrate transport apparatus 122A, 122B are not capable ofpassing each other in the transport chamber unless separate slidesystems are employed. Accordingly, the processing modules are positionedalong the length of the transport chamber so that the substrate may betransported to be processed in the processing module in a sequence whichwould avoid the transport apparatus from interfering with each other.For example, processing modules for coating may be located beforeheating modules, and cooling modules and etching modules may be locatedlast.

However, the transport chamber 18′ may have another transport zone 18A,18B which allow the two transport apparatus to pass over each other(akin to a side rail, bypass rail or magnetically suspended zone thatdoes not require rails). In this case, the other transport zone may belocated either above or below the horizontal plane(s) in which theprocessing modules are located. In this embodiment the transportapparatus has two slide rails, one for each transport apparatus. Oneslide rail may be located in the floor, or side walls of the transportchamber, and the other slide rail may be located in the top of thechamber. In alternate embodiments, a linear drive system may be employedwhich simultaneously drives and suspends the carts where the carts maybe horizontally and vertically independently moveable, hence allowingthem independent of each other to pass or transfer substrates. In allembodiments employing electric windings, these windings may also be usedas resistance heaters as in the case where it is desired that thechamber be heated for degas as in the case to eliminate water vapor forexample. Each transport apparatus in this case may be driven by adedicated linear drive motor or a dedicated drive zone in which the cartresides similar to that described before.

Referring now to FIGS. 6, and 7 there are shown other substrateprocessing apparatus in accordance with other embodiments. As seen inFIGS. 6 and 7 the transport chamber in these embodiments is elongated toaccommodate additional processing modules. The apparatus shown in FIG. 6has twelve (12) processing modules connected to the transport chamber,and each apparatus (two apparatus are shown) in FIG. 7 has 24 processingmodule connected to the transport chamber. The numbers of processingmodules shown in these embodiments are merely exemplary, and theapparatus may have any other number of processing modules as previouslydescribed. The processing modules in these embodiments are disposedalong the sides of the transport chamber in a Cartesian arrangementsimilar to that previously discussed. The number of rows of processingmodules in these case however have been greatly increased (e.g. six (6)rows in the apparatus of FIG. 6, and twelve (12) rows in each of theapparatus of FIG. 7). In the embodiment of FIG. 6, the EFEM may beremoved and the load ports may be mated directly to load locks. Thetransport chamber of the apparatus in FIGS. 6, and 7 have multipletransport apparatus (i.e. three apparatus in the case of FIG. 6, and sixapparatus in the case of FIG. 7) to handle the substrates between theload locks and the processing chambers. The number of transportapparatus shown are merely exemplary and more or fewer apparatus may beused. The transport apparatus in these embodiments are generally similarto that previously described, comprising an arm and a cart. In thiscase, however, the cart is supported from zoned linear motor drives inthe side walls of the transport chamber. The linear motor drives in thiscase provide for translation of the cart in two orthogonal axis (i.e.longitudinally in the transport chamber and vertically in the transportchamber). Accordingly, the transport apparatus are capable of movingpast one another in the transport chamber. The transport chamber mayhave “passing” or transport areas above and/or below the plane(s) of theprocessing modules, through which the transport apparatus may be routedto avoid stationary transport apparatus (i.e. picking/releasingsubstrates in the processing modules) or transport apparatus moving inopposite directions. As can be realized, the substrate transportapparatus has a controller for controlling the movements of the multiplesubstrate transport apparatus.

Still referring to FIG. 7, the substrate processing apparatus 18A and18B in this case may be mated directly to a tool 300.

As may be realized from FIGS. 3, 5 and 6-7 the transport chamber 18 maybe extended as desired to run throughout the processing facility P. Asseen in FIG. 7, and as will be described in further detail below, thetransport chamber may connect and communicate with various sections orbays, 18A, 18B in the processing facility P such as for example storage,lithography tool, metal deposition tool or any other suitable tool bays.Bays interconnected by the transport chamber 18 may also be configuredas process bays or processes 18A, 18B. Each bay has desired tools (e.g.lithography, metal deposition, heat soaking, cleaning) to accomplish agiven fabrication process in the semiconductor workpiece. In eithercase, the transport chamber 18 has processing modules, corresponding tothe various tools in the facility bays, communicably connected thereto,as previously described, to allow transfer of the semiconductorworkpiece between chamber and processing modules. Hence, the transportchamber may contain different environmental conditions such asatmospheric, vacuum, ultra high vacuum, inert gas, or any other,throughout its length corresponding to the environments of the variousprocessing modules connected to the transport chamber. Accordingly, thesection 18P1 of the chamber in a given process or bay 18A, 18B, orwithin a portion of the bay, may have for example, one environmentalcondition (e.g. atmospheric), and another section 18P2, 18P3 of thechamber may have a different environmental condition. As noted before,the section 18P1, 18P2, 18P3 of the chamber with different environmentstherein may be in different bays of the facility, or may all be in onebay of the facility. FIG. 7 shows the chamber 18 having three sections18P1, 18P2, 18P3 with different environments for example purposes only.The chamber 18 in this embodiment may have as many sections with as manydifferent environments as desired.

As seen in FIG. 7, the transport apparatus, similar to apparatus 122A,(see also FIG. 3) in the chamber 18 are capable of transiting betweensections 18P1, 18P2, 18P3 of the chamber with different environmentstherein. Hence, as can be realized from FIG. 7, the transport apparatus122A may with one pick move a semiconductor workpiece from the tool inone process or bay 18A of the processing facility to another tool with adifferent environment in a different process or bay 18B of the processfacility. For example, transport apparatus 122A may pick a substrate inprocessing module 301, which may be an atmospheric module, lithography,etching or any other desired processing module in section 18P1, oftransport chamber 18. The transport apparatus 122A may then move in thedirection indicated by arrow X3 in FIG. 7 from section 18P1 of thechamber to section 18P3. In section 18P3, the transport apparatus 122Amay place the substrate in processing module 302, which may be anydesired processing module.

As can be realized from FIG. 7, the transport chamber may be modular,with chamber modules connected as desired to form the chamber 18. Themodules may include internal walls 18I, similar to walls 18B, 18F inFIG. 2, to segregate sections 18P1, 18P2, 18P3, 18P4 of the chamber.Internal walls 18I may include slot valves, or any other suitable valveallowing one section of the chamber 18P1, 18P4 to communicate with oneor more adjoining sections. The slot valves 18V, may be sized to allow,one or more carts to transit through the valves from one section 18P1,18P4 to another. In this way, the carts 122A may move anywherethroughout the chamber 18. The valves may be closed to isolate sections18P1, 18P2, 18P3, 18P4 of the chamber so that the different sections maycontain disparate environments as described before. Further, theinternal walls of the chamber modules may be located to form load locks18P4 as shown in FIG. 7. The load locks 18P4 (only one is shown in FIG.7 for example purposes) may be located in chamber 18 as desired and mayhold any desired number of carts 122A therein.

In the embodiment shown in FIG. 7, processes 18A and 18B may be the sameprocess, for example etch, where the processing apparatus 18A and 18B incombination with tool 300 being a stocker are capable of processingequal amounts of substrates as, for example the apparatus shown in FIG.9 but without the associated material handling overhead associated withtransporting FOUPS from the stocker to individual process tools via anAMHS, and transporting individual wafers via EFEM's to the respectiveprocessing tools. Instead, the robot within the stocker directlytransfers FOUPS to the load ports (3 shown per tool, more or less couldbe provided depending on throughput requirements) where the wafers arebatch moved into locks and dispatched to their respective processmodule(s) depending on the desired process and/or throughput required.In this manner, in a steady state fashion, the FIG. 7 apparatus and FIG.9 apparatus may have the same throughput, but the apparatus in FIG. 7does it with less cost, a smaller footprint, less WIP required—thereforless inventory and with a quicker turnaround when looking at the time toprocess a single carrier lot (or “hot lot”) resulting in significantadvantages for the fab operator. The tool 18A, 18B or the stocker 300may further have metrology capability, sorting capability, materialidentification capability, test capability, inspection capability (putboxes . . . ) etc. as required to effectively process and testsubstrates.

In the embodiment shown in FIG. 7, more or less processes 18A and 18Bmay be provided that are different processes, for example etch, CMP,copper deposition, PVD, CVD, etc. where the processing apparatus 18A,18B, etc. in combination with tool 300 being, for example aphotolithography cell are capable of processing equal amounts ofsubstrates as, for example multiple apparatus, shown in FIG. 9 butwithout the associated material handling overhead associated withtransporting FOUPs from stockers to individual process tool bays and alithography bay via an AMHS, and transporting individual wafers viaEFEM's to the respective processing tools. Instead, the automationwithin the lithography cell directly transfers FOUPS, substrates ormaterial to the load ports (3 shown per process type, more or less couldbe provided depending on throughput requirements) where the substratesare dispatched to their respective process depending on the desiredprocess and/or throughput required. An example of such an alternative isshown in FIG. 7A. In this manner, the apparatus in FIG. 7 processessubstrates with less cost, lower footprint, less WIP required—thereforless inventory and with a quicker turnaround when looking at the time toprocess a single carrier lot (or “hot lot”), and with a higher degree ofcontamination control resulting in significant advantages for the faboperator. The tool 18A, 18B or the tool or cell 300 may further havemetrology capability, processing capability, sorting capability,material identification capability, test capability, inspectioncapability (put boxes . . . ) etc . . . as required to effectivelyprocess and test substrates. As can be realized from FIG. 7, theprocessing apparatus 18A, 18B, and tool 300 may be coupled to share acommon controller environment (e.g. inert atmosphere, or vacuum). Thisensures that substrates remain in a controlled environment from tool 300and throughout the process in apparatus 18A, 18B. This eliminates use ofspecial environment controls of the FOUPs as in conventional apparatusconfiguration shown in FIG. 8.

Referring now to FIG. 7A, there is shown an exemplary fabricationfacility layout 601 incorporating features of the embodiment shown inFIG. 7. Carts 406, similar to carts 22A, 122A transport substrates orwafers through process steps within the fabrication facility 601 throughtransport chambers 602, 604, 606, 608, 610, 612, 614, 616, 618, 620,624, 626. Process steps may include epitaxial silicon 630, dielectricdeposition 632, photolithography 634, etching 636, ion implantation 638,rapid thermal processing 640, metrology 642, dielectric deposition 644,etching 646, metal deposition 648, electroplating 650, chemicalmechanical polishing 652. In alternate embodiments, more or lessprocesses may be involved or mixed; such as etch, metal deposition,heating and cooling operations in the same sequence. As noted before,carts 406 may be capable of carrying a single wafer or multiple wafersand may have transfer capability, such as in the case where cart 406 hasthe capability to pick a processed wafer and place an unprocessed waferat the same module. Carts 406 may travel through isolation valves 654for direct tool to tool or bay to bay transfer or process to processtransfer. Valves 654 may be sealed valves or simply conductance typevalves depending upon the pressure differential or gas speciesdifference on either side of a given valve 654. In this manner, wafersor substrates may be transferred from one process step to the next witha single handling step or “one touch”. As a result, contamination due tohandling is minimized. Examples of such pressure or species differencecould be for example, clean air on one side and nitrogen on the other;or roughing pressure vacuum levels on one side and high vacuum on theother; or vacuum on one side and nitrogen on the other. Load locks 656,similar to chambers 18P4 in FIG. 7, may be used to transition betweenone environment and another; for example between vacuum and nitrogen orargon. In alternate embodiments, other pressures or species may beprovided in any number of combinations. Load locks 656 may be capable oftransitioning a single carrier or multiple carriers. Alternately,substrate(s) may be transferred into load lock 656 on shelves (notshown) or otherwise where the cart is not desired to pass through thevalve. Additional features 658 such as alignment modules, metrologymodules, cleaning modules, process modules (ex: etch, deposition, polishetc. . . . ), thermal conditioning modules or otherwise, may beincorporated in lock 656 or the transport chambers. Service ports 660may be provided to remove carts or wafers from the tool. Wafer orcarrier stockers 662, 664 may be provided to store and buffer processand or test wafers. In alternate embodiments, stockers 662, 664 may notbe provided, such as where carts are directed to lithography toolsdirectly. Another example is where indexer or wafer storage module 666is provided on the tool set. Re-circulation unit 668 may be provided tocirculate and or filter air or the gas species in any given section suchas tool section 612. Re-circulation unit 668 may have a gas purge,particle filters, chemical filters, temperature control, humiditycontrol or other features to condition the gas species being processed.In a given tool section more or less circulation and or filter orconditioning units may be provided. Isolation stages 670 may be providedto isolate carts and/or wafers from different process' or tool sectionsthat can not be cross contaminated. Locks or interconnects 672 may beprovided to change cart orientation or direction in the event the cartmay pick or place within a generic workspace without an orientationchange. In alternate embodiments or methods any suitable combination ofprocess sequences or make up could be provided.

Referring now to FIG. 10, there is shown an end view of an exemplarysingle axis platen drive system 320 in accordance with one embodiment.Drive system 320 is an example of a drive suitable for driving transportapparatus or carts 22A, 122A, 406 shown in FIGS. 2, 3, and 7-7A. System320 has a stationary winding set which drives platen 324. Platen 324 maybe supported on slide blocks 326 which are slideable on rails 328. Rails328 are coupled to a base 330, or side walls, of the transport chamber.Base 330 provides a barrier 332 between winding 322 and platen 324. Ascan be realized, barrier 332 may also isolate the winding 322 from theinterior environment of the chamber. Winding 322 is coupled to base 330.Platen 324 may have magnets 334 coupled to it for interfacing the platen324 with winding 322. A sensor 336 may be a magneto-restrictive typehall effect sensor and may be provided for sensing the presence of themagnets in platen 324 and determining proper commutation. Additionally,sensors 336 may be employed for fine position determination of platen324. Position feedback device 340 may be provided for accurate positionfeedback. Device 340 may be inductive or optical for example. In theinstance where it is inductive, an excitation source 342 may be providedwhich excites winding or pattern 346 and inductively couples back toreceiver 344 via coupling between pattern 346. The relative phase andamplitude relationship may be used for determining the location ofplaten 324. A cart identification tag 347, such as an IR tag may beprovided with a reader 348 provided at appropriate stations to determinecart id by station.

Referring now to FIG. 11A, there is shown an end view of platen drivesystem 400 in accordance with another embodiment. Referring also to FIG.11B, there is shown a section view of drive system 400, taken alonglines 11B-11B in FIG. 11A. As will be described further below, system400 is capable of effecting movement of a platen or cart 406 (cart 406may be similar to carts or transport apparatus 22, 122A describedbefore). System 400 has opposing stationary winding sets 402, 404 whichdrive cart 406. Winding sets 402, 404 are wound in a two dimensionaldriving array, vertical 408 and lateral 410. In alternate embodiments,additional arrays could be provided to drive cart 406 in differentdirections, for example 427 by coupling system 400 to another similarsystem oriented 90 degrees therefrom. The arrays are driven in multiplezones in order to allow multiple carts to be driven independently. As anexample, zone 424 could be a supply zone, zone 426 could be a transferzone, and zone 428 could be a return zone. Within each zone may besub-zones which allow driving multiple carts within each zone. Inalternate embodiments, more or less zones or sub-zones may be providedin any of a number of combinations. Cart 406 is supported by the fieldsproduced by winding sets 402, 404 and is positionable in a non-contactmanner by biasing the fields between winding sets 402 and 406. Chamber412 may be provided as a barrier 414 between winding sets 402, 404 andcart 406. Windings exist in zone 416 as shown. Cart 406 may have platens418, 420 with the windings. In alternate embodiments, more or lessplatens may be provided. Arrays of sensors may be provided for sensingthe presence of the magnets in the platens or the cart or the platensfor determining proper commutation and location and for fine positiondetermination of the platens and the cart. A cart identification tag maybe provided with a reader provided at appropriate stations to determinecart id by station.

Referring now to FIG. 12, there is shown a top view of an exemplary cart229 for the processing apparatus 10 in accordance with anotherembodiment of the apparatus. Cart 229 may be similar to transportapparatus 22 or carts 122A, 406 described before and shown in FIGS. 2,3, and 7-7A. Cart 229 is shown as being capable of transportingsubstrate 148 along an axial path 150 and/or a radial path 152. The cart229 is also capable of moving the substrate along path 154 shown in FIG.12. Cart 229 is shown as a two dimensional system for simplicity,however in alternate embodiments additional axis of motion, for example,z motion (not shown—in and out of paper) or angular motion 154 could beprovided. Cart 229 is shown as being capable of handling a singlesubstrate 148 for simplicity. However, in alternate embodiments,additional handling could be provided. For example, the cart may includecapability to handle a second substrate, as in the case where it isdesired that a substrate be exchanged at a process module (i.e. a first,processed substrate may be picked and a second unprocessed substrate maythen be placed at the same process module from the same cart 229).

Cart 229 has frame 156, end effector 158 and secondary frame 160. Slides162 constrain frame 156, end effector 158 and secondary frame 160 to beslideable relative to each other along linear path 152 either to theleft or right of frame 156 as shown. Although a linear mechanism isshown, in alternate embodiments, any suitable arm system may be usedsuch as, for example, a scara type arm coupled to frame 156 as shown inFIG. 17 and as will be described in greater detail below. Substrate 148is supported on end effector 158.

Referring now to FIG. 12A, there is shown a top view of exemplary cart229, in a portion of a chamber (similar to chamber 18 and 602-626, seeFIGS. 2-3, and 7-7A). The cart has the end effector 158 extended intoexemplary module 166. Module 166 may be similar to any of the modulesdescribed before as being connected to the transport chamber. Cart 229is shown as being capable of transporting substrate 148 along an axialpath 150 and/or a radial path 152. Cart 229 has frame 156, end effector158 and secondary frame 160. Slides 162 constrain frame 156, endeffector 158 and secondary frame 160 to be slideable relative to eachother along linear path 152 either to the left or right of frame 156 asshown. Frame 156 has magnet platens 168 on its underside which interfacewith synchronous motor 170. Drive platen 172 interfaces with synchronousmotor 174. Drive platen 172 is mounted on the underside of and slideablerelative to frame 156 along direction 176 which is substantiallyparallel to direction 150 by using bearings 178. Movement of platens 168and 172 simultaneously along direction 150 allows cart to move indirection 150 without motion in direction 152. Holding platens 168stationary while simultaneously moving platen 172 along direction 176relative to frame 156 causes a radial motion along direction 152 ofsubstrate and end effector 148, 158.

Linear motion of platen 172 in direction 176 is translated into linearmotion of secondary frame 160 along direction 152. Pulley 186 isrotatably coupled to frame 156 and has secondary pulleys 188 and 182.Pulley 182 is coupled to platen 172 with bands 184 such that movement ofplaten 172 along direction 180 causes pulley 182 to rotate in direction190 with the opposite applying in opposing directions. Pulleys 192 and194 are rotatably coupled to frame 156. Cable 196 is coupled to pulley188 at point 198, wraps around pulley 192 as shown, and terminates at200 on secondary frame 160. Cable 202 is coupled to pulley 188 at point198, wraps around pulley 188 counterclockwise, wraps around pulley 194as shown and terminates at 204 on secondary frame 160. In this manner,linear motion of platen 172 in direction 176 is translated into linearmotion of secondary frame 160 along direction 152.

Linear motion of platen 172 in direction 176 and the translated linearmotion of secondary frame 160 along direction 152 also further extendsend effector 158 in direction 152 as shown. Pulleys 210 and 212 arerotatably coupled to secondary frame 160. Cable 214 is coupled to endeffector 158 at point 216, wraps around pulley 210 as shown, andterminates at 218 on frame 156. Cable 220 is coupled to end effector 158at point 222, wraps around pulley 212 and terminates at 224 on frame156. In this manner, linear motion of platen 172 in direction 176 istranslated into linear motion of secondary frame 160 along direction 152which is further translated to further extension of end effector 158 indirection 152 as shown. In lieu of cable pulleys, the transmissionsbetween platens and end effectors may use belts, bands or any othersuitable transmission means made of any suitable materials. In alternateembodiments, a suitable linkage system may be used in place of cablepulleys to transmit motion from the platens to the end effectors.Retraction of the end effector 158, to the position shown substantiallyin FIG. 12, is accomplished in a similar but reverse manner. Further,extension of the end effector 158 to a position similar to but oppositefrom that shown in FIG. 12B is effected by moving platens 168, 172 in anopposite manner to that described above.

Referring now to FIG. 12B, there is shown an end view of cart 229 beforebeing extended into exemplary process module 166. Slides 240 constrainframe 156 to be slideable along linear path 150 as shown. Frame 156 hasmagnet platens 168 on its underside which interface with synchronousmotor 170. Drive platen 172 interfaces with synchronous motor 174. Driveplaten 172 is mounted on the underside of and slideable relative toframe 156 along a direction which is substantially parallel to directionindicated by arrow 150 (see FIG. 12). Movement of platens 168 and 172simultaneously along direction 150 allows the cart to move in directionindicated by arrow 150 without motion in direction 152. Holding platens168 stationary while simultaneously moving platen 172 along direction176 relative to frame 156 causes a radial motion along direction 152 ofsubstrate and end effector 148, 158. Platens 172 and 168 may havemagnets that interface with motors 170 and 174. Chamber 244 may be madefrom a nonmagnetic material, for example non-magnetic stainless steeland provide a barrier 246, 248 between the motor windings and theirrespective platens. In alternate embodiments, more or less linear drivesor carts may be provided. For example, a single drive motor may beprovided having additional drive zones where platens 168 and 172 wouldinterface with the same drive motor but be independently driveable bythe different zones. As a further example, additional carts could bedriven by different drive systems in the floor 250, the walls 252, 254above in line with or below the slot openings or in the cover 256 of thechamber.

Referring now to FIG. 13A, there is shown a portion of chamber 716 ofthe apparatus 10, and a top view of an exemplary drive system 701 withan exemplary cart 700 that may be used with the apparatus. Chamber 716is another representative portion of chamber 18, or chambers 602-624 ofthe apparatus (see FIGS. 2-3, and 7-7A). Cart 700 is shown as beingcapable of transporting substrates 702A, 702B along an axial path 704and/or a radial path 706 or in a Z motion (not shown—in and out ofpaper). In alternate embodiments, angular motion could be provided. Inalternate embodiments, more or less substrate handling could beprovided. Cart 700 has transport mechanisms 724A and 724B which can be alinear mechanism or any suitable arm system may be used such as, forexample, a scara type arm. In alternate embodiments no arm may beprovided. Transport mechanisms 724A and 724B may extend into processmodules or other modules as desired in a manner similar to that shown inFIG. 12A. Cart 700 has platens 722, 720, 710 and 712 on its sides whichinterface with synchronous motors in the walls of transport chamber 716.Drive platen 712 is mounted on the side of cart 700 and is slideablerelative to cart 700 along direction 704. Platen 712 drives mechanism724A such that the movement of platen 712 along direction 704 (fromlocation 712A to 712B, see FIG. 13A) relative to cart 700 allowsmechanism 724A to transport wafer 702A between location 708A and 708Bthrough slots 718A and 718B. Similarly, drive platen 710 is mounted onthe side of cart 700 and is slideable relative to cart 700 alongdirection 704. Platen 710 drives mechanism 724B such that the movementof platen 710 along direction 704 (from location 710A to 710B, see FIG.13A) relative to cart 700 allows mechanism 724B to transport wafer 702Bbetween location 708A and 708B through slots 718A and 718B. Platens 710and 712 are independently moveable relative to cart 700. Platens 722,720 are fixed relative to cart 700. Holding platens 720, 722 stationarywhile simultaneously moving platen 712 along direction 704 causes aradial transfer motion along direction 706. Holding platens 720, 722stationary while simultaneously moving platen 710 along direction 704also causes a separate radial transfer motion along direction 706.Simultaneously moving platens 720, 722, 710 and 712 along direction 704causes cart 700 to move along direction 704—enabling the cart 700 tomove from process location to process location as through valve 714 forexample.

Referring now to FIG. 13B, there is shown a section view of theexemplary drive system 701 and cart 700 taken along line 13B-13B in FIG.13A. Referring also to FIG. 13C, there is shown another side sectionview of the exemplary drive system 701 in FIG. 13B. System 701 hasopposing stationary winding sets 727, 729 that drive cart 700. Windingsets 727, 729 are wound in a combination of one and two dimensionaldriving arrays, for example, vertical 705 and lateral 704. The drivingarrays may be linear motors or linear stepping type motors in one or twodimensional arrays. Examples of such driving arrays are described inU.S. Pat. Nos. 4,958,115, 5,126,648, 4,555,650, 3,376,578, 3,857,078,4,823,062, which are incorporated by reference herein in their entirety.In alternate embodiments, integrated two dimensional winding sets couldbe employed with platens having two dimensional magnets or patterns. Inother alternate embodiments, other types of one or two dimensional drivesystems could be employed. In alternate embodiments, additional arrayscould be provided to drive cart 700 in different directions, for exampleby coupling system 701 to another similar system oriented 90 degreestherefrom. The arrays are driven in multiple zones in order to allowmultiple carts to be driven independently. As an example, zone 685 couldbe a supply zone, zone 683 could be a transfer zone, and zone 681 couldbe a return zone. Within each zone may be sub-zones which allow drivingmultiple carts within each zone. In alternate embodiments, more or lesszones or sub-zones may be provided in any of a number of combinations.Cart 700 is supported by the fields produced by winding sets 727, 729and is positionable in a levitated and non-contact manner by biasing thefields between winding sets 727 and 729. FIG. 13C shows one possiblewinding combination that could be driven by the system shown in FIG. 13Dand employed to levitate cart 700 (as for example as discussed furtherbelow with reference to FIG. 14A, or through multiple axis activelevitation). One dimensional winding sets are provided in winding zones732A-C and 730A-C and 734A-C and 742A-B and 740A-B. Two dimensionalwinding sets are provided in winding zones 736A-E and 738A-C. Inalternate embodiments, any suitable combination of winding sets could beprovided or a full 2-D array or otherwise could be provided. Cart 700has platens 720 and 710 which may be used in combination with arrays738B for platen 720 and arrays 736B, C and D for platen 710. By movingplaten 710 in direction 704 (see FIG. 13A) and holding platen 720stationary, a wafer may be radially moved through slot 718A. Bysimultaneously moving 710 and 720 in direction 705 (see FIG. 13B), awafer may be picked or placed. By coordinating winding commutation andwinding switching between zones, cart 700 may selectively be movedvertically and/or laterally through the different winding and drivezones. Chamber 716 may be provided as a barrier between winding sets727, 729 and cart 700. In alternate embodiments, no barrier need exist,such as in the event that winding sets 727, 729 are inside the enclosure716 where there is for example a clean air or nitrogen environment. Inalternate embodiments, more or less platens or windings may be provided.Arrays of sensors 746, 747, 748 may be provided for sensing the presenceof the magnets in the platens or the platens or the cart(s) fordetermining proper commutation and location and for fine positiondetermination of the platens and the cart or for determining positions,such as the gap between platens and windings. A cart identification tag,as noted before, may be provided with a reader provided at appropriatestations to determine cart id by station.

Referring now to FIG. 14A there is shown an end view of anotherexemplary cart 760, in accordance with yet another embodiment, supportedby the fields produced by single axis linear motor winding sets 762,764. Exemplary cart 760 is positionable in a non-contact manner bybiasing 776 the fields between winding sets 762 and 764. Positionsensing 766, 768 is provided, in a close loop fashion with biasing 776,to levitate cart 760. Levitation may be accomplished in this simplemanner as the cart is passively stabilized in the Z direction as shownin FIG. 14B. Cart 760 has magnet platens 772 and 774 on its sides whichmay have magnets or be made from magnetic or conductive materials whichinterface with winding sets 762, 764. In alternate embodiments, more orless platens could be provided, driving arms for example. Chamber 770(similar to any representative portion of the chambers 18, 602-624 ofthe apparatus, see FIGS. 2-3, and 7-7A) may be made from a nonmagneticmaterial, for example non-magnetic stainless steel and provide a barrierbetween the motor windings and their respective platens as describedbefore. In alternate embodiments, more or less linear drives or cartsmay be provided. For example, a single drive motor may be providedhaving additional drive zones where platens would interface with thesame drive motor but be independently driveable by the different zones.As a further example, additional carts could be driven by differentdrive systems in the floor, the walls above in line with or below slotopenings or in the covers of the chamber.

In FIG. 14B the relationship between a passive restoring force F and anaxial deflection Z from the desired position of cart 760 is graphicallyillustrated. The passive restoring force is generally due to thepresence of ferromagnetic material, for example, as part of the cart760, the winding sets 762 764, etc. In the respective positive ornegative axial direction (z direction) the passive restoring force firstincreases in magnitude to a value FMAX or −FMAX respectively up to amaximal deflection ZMAX or −ZMAX respectively, but decreases againhowever when this deflection is exceeded. Therefore, if a deflectiveforce is applied to cart 760 (such as, for example, cart weight orexternal forces, such as from other winding sets that drive the same orother platens or otherwise) that exceeds FMAX, then the cart may escapefrom the windings 762, 764. Otherwise, cart 760 will stay within thefields as long as they are applied. This principle, described in USpatent references (which are hereby incorporated by reference in theirentirety) U.S. Pat. Nos. 6,485,531, 6,559,567, 6,386,505, 6,351,048,6,355,998 for a rotary devices is applied in the drive system 701, ofthe apparatus described herein, in a linear fashion to levitateexemplary cart 760. In alternate embodiments, other drive systems orlevitation systems may be used.

Referring again to FIG. 13D, there is shown a diagram of an exemplarywinding drive system 790 suitable for use with cart/platen drive system701 in FIG. 13A. Winding drive system 790 has windings 792, multiplexer793 and amplifier modules 794. Windings 792 may have windings and/orsensors such as hall sensors, positions sensors, inductive sensors,carrier identification sensors, status and fault detection logic andcircuitry or otherwise. Amplifier modules 794 may have single ormultiple phase amplifiers, position and/or presence sensor inputs oroutputs, CPUs and/or memory, identification reader inputs or outputs,status and fault detection logic and circuitry or otherwise. Amplifiermodules 794 may connect directly to windings 792 or through multiplexerunit 793. When using multiplexer unit 793, amplifiers A1-Am may beselectively connected to any of windings W1-Wn. A CPU coordinates thisselective connection and monitors the status of the devices. In thismanner, the CPU may selectively take amplifier modules or windings offline for service without shutting down the tool.

As noted before, the transport apparatus suitable for use in thetransport chambers 18, 602-624 or carts (see for example FIGS. 2-3, and7-7A) may comprise carts with or without a transfer arm for transferringsemiconductor workpieces between the cart and a desired location in theapparatus. FIGS. 12 and 13A respectively show, as described before, twoexemplary embodiments of transport carts 229, 700 with transfer arms forhandling semiconductor workpieces in the apparatus. Referring now aheadto FIGS. 22 and 23, there is shown another embodiment of a transportcart mechanism 1557 suitable for use in the chambers of apparatus 10.Cart 1557 may include base section or base plate 1558 and transfer arm1577 mounted to the base plate. As shown in FIG. 22, the cart mechanismbase plate 1558 with two coupled magnet arrays 1502 on opposite sides ofthe plate, but not limited to opposite corners of the plate. On theopposing corners of the robot base plate 1558, two addition magnetarrays 1502 are coupled to linear bearing carriages 1560 and are made toslide on linear bearing rails 1562. These linear bearing rails 1562 arecoupled to the base plate 1558. A drive belt 1564 or other means ofconverting linear motion to rotary motion is attached to the linearbearing carriage 1560. In the case shown, the drive belt 1564 is wrappedaround an idler pulley 1566 and then a pulley tensioner 1568 andattached to a drive pulley 1570. The linear motion applied to thebearing carriage 1560 through the magnet array 1502, will result inrotary motion of the driven pulley 1572. In the case of a two degree offreedom application, a redundant version of the mechanism described isapplied to the opposite side of the robot cart mechanism and a duplicatecircuit is attached to drive pulley 1572. This combination yields aconcentric pulley assembly. The relative motion between the fixed magnetarray 1502 and the combined magnet array 1502 and linear bearingcarriage 1560 provides a means of driving the transfer arm linkage. Inthe case of linear transport of the robot carriage, the linearbearing/magnet array 1560/1502 and the coupled magnet array/cart baseplate 1502/1558 are driven as a fixed set and no rotation of the drivenpulleys 1570 & 1572 is seen. The drive mechanism of base plate 1558 maybe used for operating other suitable transfer arm linkages, someexamples are shown in FIGS. 24-24C, 25-25C. The transfer arm 1577 in theembodiment shown in FIG. 23, has a general single SCARA armconfiguration. Drive pulley 1572 is coupled to the lower link arm 1574and drive pulley 1570 is tied to forearm drive pulley 1586. The rotationmotion of the forearm pulley 1586 is coupled to the forearm 1578 throughthe drive belt 1582 and the elbow pulley 1576. The wrist lend effector1584 is driven by the resulting relative rotation motion of the forearm1578 with respect to the wrist elbow pulley 1580 as it is grounded tothe lower link arm 1574. Typically, this motion is achieved by thepulley ratio at each joint with respect to the input drive ratio ofpulleys 572 and 1570. Referring also to FIGS. 23A-23B, the transfer armlinkage 1577 is shown respectively in retracted and extended positions.The movement between retracted and extended positions is achieved (in amanner as described above) by moving the movable magnet arrays 1502 asdesired relative to the base plate. The movement of the arm linkage maybe performed with the cart stationary or moving relative to thetransport chamber. FIGS. 23A-23B show the transfer arm 1577 positionedso that when extended the arm 1577 extends to the lateral side 1576R(i.e. the side of the cart facing a chamber wall) of the cart. This issimilar to the extension/retraction movement of the transfer mechanism724A, B of cart 700 in FIG. 13A. As can be realized, the transfer arm1577 on cart 1557 may be rotated as a unit (using movable magnet arrays1502) about axis of rotation S (see FIG. 22) to any desired orientationrelative to the cart base plate. For example, if rotated about 180° fromthe orientation shown in FIGS. 23A-23B, the transfer arm 1577 may beextended to the opposite side 1575L from side 1575R shown in FIG. 23B.Further, the transfer arm may be rotated about 90° so that the armextension is along the linear direction of the chamber (indicated byarrow 15X in FIG. 22). Any number of arm linkages may be employed withsuch a cart. Other examples of suitable arm linkages that may be usedwith the cart are described in U.S. Pat. Nos. 5,180,276; 5,647,724;5,765,983; and 6,485,250 all incorporated by reference herein in theirentirety.

FIG. 24 is an elevation view of another embodiment of the cart mechanism1557′ with dual rotary end effectors mounted to the cart base plate1558′. Cart 1557′ is otherwise similar to cart 1557 described before andshown in FIGS. 22-23. Similar features are similarly numbered. FIGS.24A-24C show the use of both linear transport and couple relative motionof the bearing carriage array as the cart is moving. As described beforewith reference to FIG. 22, the rotation of pulleys 1570′ and 1572′results from the bearing carriage and magnet array moving with respectto the fixed magnet arrays which are coupled to the cart's base plate.In the combined case, the robot cart transport is moving along thelinear chamber, in the direction indicated by arrows 15X′, and thebearing carriage and magnet array move with respect to the groundedarrays. This motion enables the end effector (s) 1588′ and 1590′ torotate thereby causing the robot end effector to extend substantiallyperpendicular to the linear direction of the cart similar to FIGS.23A-23B, described before. FIGS. 24A-24C show the end effectors 1588′and 1590′ extended to one side for example purposes. As can be realizedhowever, the end effectors 1588′, 1590′ may be extended to any side ofthe base plate. Further, the end effectors 1588′, 1590′ may be extendedto a position where the end effector is oriented at an angle more orless than about 90° as shown in FIGS. 24A-24C.

FIG. 25 is a schematic elevation view of still another embodiment of thecart 1557″, having and arm linkage similar to that shown in FIG. 23. Inthis case, the drive pulley 1572″ is attached to the lower link arm1592″. The driver pulley 1570″ is coupled to the end effector driverpulley 1600″ and coupled to the elbow pulley 1596″ through a drive belt1598″. The elbow drive pulley is attached to the robot end effector1594″ and provides a means of transmitting the rotation of driver pulley1570″ to the driven end effector 1594″. FIGS. 25A-25C show the cart withthe arm linkage in three different positions. FIGS. 25A-25C show the endeffector 1594″ extended to one side of the base plate 1558″ of the cartfor example purposes only. Similar to the transfer arms shown in FIGS.22-23 and 24, the transfer arm 1577″ may be rotated about axis S″ sothat the end effector may be extended/retracted in any directionrelative to the base plate 1558″ of the cart 1557″. With reference nowalso to FIGS. 2-7A, a significant advantage of using carts (such ascarts 22, 122A, 406, 229, 700, 1557, 1557′, 1557″ shown in FIGS. 12,13A, 22, 23, 24, and 25) with articulate transfer arms is that for agiven reach of the transfer arm, the transfer chamber may be providedwith the minimum width. The multi-axis articulation of the transfer armson the different cart embodiments, allows substantially independentplacement of the cart relative to the path of the articulating arm,which in turn allows the width of the transport chamber 18 to be reducedto a minimum. Similarly, the width of slot valves and passagesconnecting storage processing modules to the transport chamber may bereduced to minimum size.

Referring now to FIG. 15, an exemplary wafer aligner 500 for use withapparatus 10 is shown. The wafer aligner carrier 500 may generallyinclude two parts, wafer chuck 504 and the wafer transport carrier 502.The aligner provides wafer alignment and movement within the linearCartesian transport tool. The aligner is made to interface with thetransport cart(s) in the apparatus (such as for example carts 22, 122A,406, 700, 1557) or in some cases may be included in the robot cart ofthe linear process tool architecture.

Referring also to FIG. 16, the wafer chuck 504 is shown to be able toseparate from the wafer transport carrier 502. Friction pads may couplethe two devices during transport throughout the linear Cartesianapparatus. When disassembled, the wafer chuck 504 is free to rotate withrespect to the wafer transport carrier 502. The wafer chuck 504 providesa means of passive wafer edge support by using angle ramped wafer edgepads 508 with respect to the substrate (wafer) 506. An additionalfeature as part of the wafer chuck 504 is the relief beneath the wafer506 for the ability of the robot arm cart to remove and place the waferonto the wafer carrier 500. This is identified as wafer removalclearance zone 510.

This method of wafer rotation with respect to the linear transport cartcan be applied directly to the robot's end effector. This method isshown in FIG. 17. The robot arm cart 534 is configured so that the waferchuck 504 is removable from the robot's end effector 536. In this case,the chuck is free to be rotated to correct for any slight wafer notchorientation requirements based on drop off point changes found in theprocess modules or load locks.

Referring also to FIG. 18, the wafer chuck rotation device 532 is shown.At multiple points within the linear transport tool, these rotationalwells can be deployed. This device is based on motor isolationtechniques found in U.S. Pat. No. 5,720,590 which is hereby incorporatedby reference in its entirety. In alternate embodiments, a conventionalmotor and seal combination may be used. A stationary motor 522 ismounted to the linear transport chamber's base 530. A vacuum isolationbarrier 520 is placed between the motor armature 540 and the magnetarray 524. The magnet array is mounted directly to the rotation shaft542. This allows for direct drive coupling into the vacuum system. Apossible support bearing 518 may be required but ideally, magneticsuspension is used. An optical encoder disc 526 is attached to therotation shaft 542 with the read head 528 placed in a location toprovide position feedback to the controller for the rotation shaft's 542angle. The aligner chuck 504 is lowered onto the friction pads orkinematics pin(s) 516. These pads/pins provide a means of wafer chuck504 rotation once the wafer chuck 504 is disconnected from the wafercarrier 502 or the robot's end effector 536. This same means ofproviding rotation can be applied to control the rotational position ofa robotic arm link 538 applied as part of the robot arm carrier shown inFIG. 17.

Referring also to FIG. 19, the wafer transport carrier 500 including thewafer chuck 504 and the wafer transport carrier is moved to a positionabove the wafer chuck rotation device 532. In FIG. 20, the wafertransport carrier is lowered such that the wafer chuck 504 is lifted offon the transport carrier 502. A camera 544 located in the transport'schamber lid 546 is able to look at the image of the wafer and identifythe wafer's x-y position and the location angle of the wafer's notch.The wafer carrier can then be moved to provide x-y location change ofthe wafer chuck 504 with respect to the wafer transport carrier 502 androtation can be provided to correct for notch alignment. Another optionfor the wafer chuck rotational drive when used as a method of robot armcarrier device is to allow rotational engagement while extending therobot link arm and requiring vertical axis of motion to allow for thesubstrate or wafer to be lowered/raised from the process module or loadlock. A method of this approach is schematically shown in FIG. 21. Astationary motor 522 is mounted to a guided plate 548. The guided plateis attached to the linear transport chamber's base 530 via a metalbellows 550 or other linear isolation seal (lip seal, o-ring, etc.). Avacuum isolation barrier 520 is placed between the motor armature 540and the magnet array 524. The magnet array is mounted directly to therotation shaft 542. This allows for direct drive coupling into thevacuum system. A possible support bearing 518 may be required butideally, magnetic suspension is used. An optical encoder disc 526 isattached to the rotation shaft 542 with the read head 528 placed in alocation to provide position feedback to the controller for the rotationshaft's 542 angle. An additional guide roller 552 and the supportingstructure 554 with end of travel stop 556 allow the rotation drive to beheld positioned as required to engage the wafer chuck or robot armrather than using the linear wafer transport carrier 500 as theactuation device. In the case where the transport chamber is pressurizedresulting in a state where the robot drive is positioned up, the forceof the bellows will act as a spring and allows the rotational device tobe engaged with various linear robot arm cart vertical elevations (suchas during a pick or place) but over a practical limited vertical travelrange. Once the device is engaged the friction pads or kinematics pin(s)516. These pads/pins provide a means of wafer chuck 504 rotation oncethe wafer chuck 504 is disconnected from the wafer carrier 502 or therobot's end effector 536 as shown in FIG. 20. This same means ofproviding rotation can be applied to control the rotational position ofa robotic arm link 538 applied as part of the robot arm carrier shown inFIG. 17.

Systems, such as those shown in FIGS. 2-7, may be controlled byconfigurable and scaleable software stored in controller C. Referringnow also to FIG. 26, there is shown manufacturing execution (“MES”)system software that may be provided in the controller C communicablyconnected to the processing system. The MES system 2000 comprisessoftware modules 2002-2016 or options that enhance the capabilities ofthe MES. The modules include a material control system (“MCS) 2002, areal time dispatcher (“RTD”) 2004, a workflow or activity manager (“AM”)2006, an engineering data manager (“EDA”) 2008 and a computermaintenance management system (“CMMS”) 2010.

The MES 2002 allows manufacturers to configure their factory resourcesand process plans, track inventory and orders, collect and analyzeproduction data, monitor equipment, dispatch work orders tomanufacturing operators, and trace consumption of components intofinished products. The MCS software module 2002 allows the manufacturerto efficiently schedule individual carts (for example, carts 22, 122A,406, 228, 700, 1557 in FIGS. 2-3, 7-7A, 12, 13A and 22) to arrive at theprocessing tools to maximize overall system efficiency. The MCSschedules when an individual cart will arrive at, and depart from, aspecified processing tool (for example, process 18A, 18B in FIG. 7, andmodules 602-626 in FIG. 7A). The MCS manages any queuing and routingrequirements at each processing tool and optimizes the system yieldwhile minimizing the cart transport cycle time.

The RTD 2004 allows manufacturers to make cart routing decisions, inreal time, based on feed back from the health of the processing tools.Additionally, cart routing decisions may be made by the MES operator.The MES operator may change the priority in which specific products needto be manufactured.

The AM 2006 allows manufacturers to monitor the progress of any givencart holding one or more substrates though the entire manufacturingprocess. If a processing tool generates an error, the AM 2006 determinesthe best remaining route for all the substrates being processed at theprocessing tool. The EDA 2008 allows manufactures to analyze themanufacturing data and execute statistical process control algorithms onthat data in an effort to improve the efficiency of the processing tool.The CMMS 2010 system allows the manufacturer to predict when maintenanceis required on an individual processing tool. Variances in the processof the processing tool is monitored and compared against known processresults and changes to the process or scheduled repairs to theprocessing tool is predicted.

Exemplary drive systems for controlling the movement of transportapparatus 22 will now be disclosed. Transport apparatus 22A may besimilar to transport apparatus 122A, 122B, cart 406, and carts 229, 700described above. The drive systems may be embodied as linear motorsutilizing electromagnetic principles to affect various degrees offreedom of transport apparatus 22, providing propulsion, lift andguidance control, yaw, pitch and roll stabilization, and arm actuation.

The exemplary drive systems may be embodiments of linear motor 30 (FIG.2) and the zoned linear motor drives described above. The embodimentsoffer reduced complexity, lower cost and higher reliability at least byminimizing the number of active components, such as motor windings andcontrol electronics. In particular, the number of the degrees of freedomthat require active and closed-loop control are minimized, separatededicated guidance windings are eliminated, and control is decoupled sothat it may be implemented using conventional two-channel motoramplifiers. Additionally, the efficiency of the system is improved dueto utilization of passive magnetic forces in some embodiments, thusreducing cooling requirements and operating costs.

Referring to the exemplary embodiment in FIG. 27, the drive systemsdisclosed herein generally include at least one permanent magnet 2700coupled to transport apparatus 22, stationary windings 2710 thatinteract with the magnetic field of the permanent magnet, and controlelectronics 2715 for driving stationary windings 2710.

Control electronics 2715 may include a CPU 2720 with at least onecomputer readable medium 2725 having programs for controlling controlelectronics 2715. A multiplexer 2730 and other drive electronics 2735including amplifiers for driving the stationary windings may also beutilized. An interface 2745 may be included for receiving commandsrelated to transport apparatus position or a force to be applied.Commands may be received from a user, from a controller of the substrateprocessing apparatus, or from a control system controlling a number ofsubstrate processing apparatus.

Control electronics 2715 drive stationary windings 2710 resulting in theapplication of forces on permanent magnet 2700 and correspondingly ontransport apparatus 22. Thus, control electronics 2715 drive thestationary windings to actively produce desirable propulsion, lift andguidance forces for open and closed-loop coordinate control of transportapparatus 22. The applied forces may cause transport apparatus 22 tomove within transport chamber 18 or may cause transport apparatus 22maintain a holding position. The drive systems described herein are alsosuitable for use with transport chambers 18, 602-624, 716 or any othertransport chamber.

The drive system electronics may also include sensors for detecting theposition of transport apparatus 22. The sensors may sense the proximityof the at least one permanent magnet 2700 or may include other positionfeedback devices for determining a position of the transport apparatus22 within transport chamber 18.

The drive system embodiments may also include ferromagnetic componentsthat include stationary ferromagnetic elements and permanent magnet2700, arranged so that the stationary ferromagnetic elements interactwith the magnetic field of permanent magnet 2700. The stationaryferromagnetic elements, which may be present in selected embodiments,provide passive magnetic forces that either fully stabilize a subset ofthe degrees of freedom of transport apparatus 22 or help balance theweight of transport apparatus 22. These passive forces may also providea means of safe touchdown on power loss.

At least some of the positions or coordinates of transport apparatus 22and the forces acting on transport apparatus 22 may be defined in thecontext of a three axis coordinate system (x, y, z) where the x axisindicates a propulsion direction, the y axis indicates a guidancedirection perpendicular to the propulsion direction, and the z axisindicates a lift direction, generally a vertical direction, where the x,y, and z axes are all orthogonal to each other. In FIG. 27, the x and yaxes are shown while the z axis extends perpendicular to the surface ofthe page.

FIGS. 28A-28D and 29A-29C show embodiments similar to FIG. 27 withdifferent winding configurations.

FIGS. 28A-28D show, in schematic form, the transport apparatus 22together with a drive system embodiment that provides passive lift,pitch and roll stabilization, and closed-loop propulsion, guidance andyaw control. FIG. 28A shows a cross section while FIG. 28B shows a frontor rear view of transport apparatus 22 in transport chamber 18. Activemagnetic forces are provided by independent stationary windings 2800 in,for example, two locations adjacent to a surface 2810 of transportchamber 18.

The positions and forces may be described using the followingnomenclature and units of measure:

-   -   x=position of the transport apparatus 22 along the x axis (m)    -   y=position of the transport apparatus 22 along the y axis (m)    -   y_(F)=position of the front of the transport apparatus 22 along        the y axis (m)    -   y_(R)=position of the rear of the transport apparatus 22 along        the y axis (m)    -   z=position of the transport apparatus 22 along the z axis (m)    -   F_(x)=Total force in x-direction on the transport apparatus 22        (N)    -   F_(y)=Total force in y-direction on the transport apparatus 22        (N)    -   F_(z)=Total force in z-direction on the transport apparatus 22        (N)    -   M_(x)=Moment about the x-axis (Nm)    -   R_(x)=Rotation about the x-axis (rad)    -   M_(y)=Moment about the y-axis (Nm)    -   R_(y)=Rotation about the y-axis (rad)

While shown as one side of transport chamber 18, surface 2810 may be afloor, a side, a ceiling, or any other surface of transport chamber 18.Transport chamber 18 may be made from a nonmagnetic material, forexample non-magnetic stainless steel and surface 2810 may provide abarrier between windings 2800 and transport apparatus 22.

Magnets 2815, 2820 may be disposed on opposing sides 2825, 2830,respectively, of transport apparatus 22. Stationary ferromagneticelements 2835, 2840 may be situated proximate to magnets 2815, 2820,respectively. In some embodiments, stationary ferromagnetic elements2835, 2840 may be formed as part of an iron core or iron backing of thewindings 2800, or may be incorporated as part of the structure oftransport chamber 18. In other embodiments, stationary ferromagneticelements 2835, 2840 may reside on the exterior or the interior oftransport chamber 18. The ferromagnetic components that include thestationary ferromagnetic elements 2835, 2840 and the magnets 2815, 2820interact to generally provide passive stabilizing forces including oneor more of lift, pitch, roll, guidance, and yaw forces.

Transport apparatus 22 may include one or more position feedback devices2845, 2850 and transport chamber 18 may include one or more sensors2855, 2860. Position feedback devices 2845, 2850 may be similar toposition feedback device 340 (FIG. 10), and sensors 2855, 2860 may besimilar to sensor 336 (FIG. 10) described above.

In this embodiment and the embodiments disclosed herein, sensors orarrays of sensors 2885, 2890 may be provided for sensing the presence ofthe magnets, for example magnets 2815, 2820 or any arrangement ofmagnets or magnet platens coupled to the transport apparatus in itsvarious forms. Sensors 2885, 2890 may also sense the transport apparatusitself or ferromagnetic material that may be part of the transportapparatus. The sensors may be used for determining the location in one,two, or three dimensions. The location information may then be used fordetermining proper commutation of the winding of the transport apparatus22.

Control electronics 2715 (FIG. 27) drive the stationary windings 2800 ina manner that provides closed loop control of the x, y_(F), and y_(R)coordinates of transport apparatus 22, where y_(F) represents theposition of the front 2865 of the transport apparatus 22 and y_(R)represents the position of the rear 2870 of the transport apparatus 22.The combination of ferromagnetic components including magnets 2815,2820, and stationary ferromagnetic elements 2835, 2840 provide passivecontrol of the z, R_(x), and R_(y) position coordinates.

In some embodiments, the combination of ferromagnetic componentsincluding magnets 2815, 2820, and stationary ferromagnetic elements2835, 2840 may operate to apply passive forces on transport apparatus22, and control electronics 2715 driving stationary windings 2800operate to apply Lorentz or Maxwell forces on transport apparatus 22 asfollows:

-   -   F_(x)=F_(xRF)+F_(xRR), applied as Lorentz forces;    -   F_(yF)=F_(yLF)+F_(yRF), F_(yR)=F_(yLR)+F_(yRR); where F_(yLF),        F_(yLR) are applied as passive forces and F_(yRF), F_(yRR) are        applied as Maxwell and/or Lorentz forces; and    -   F_(z), M_(x), M_(y), applied as passive forces.

FIG. 28C illustrates some of the position coordinates and forces appliedto the transport apparatus 22.

FIG. 28D illustrates some of the position coordinates and forces appliedto the transport apparatus 22 when the transport apparatus includes twoparts, for example, for implementing movement similar to cart 229 (FIG.12A) described above. Actuation may be implemented by driving theindependent windings individually causing relative motion of front 2875and rear 2880 sections of transport apparatus 22. This may beaccomplished with no additional amplifier channels.

In the embodiments shown in FIGS. 28A-28D, motion in the z-direction maybe provided by an additional device.

FIGS. 29A-29C show an exemplary embodiment of a drive system thatprovides passive lift, pitch and roll stabilization of transportapparatus 22, along with closed-loop propulsion, guidance and yawcontrol. FIG. 29A shows a cross section while FIG. 29B shows a front orrear view of transport apparatus 22 in transport chamber 18. The closedloop controlled forces are provided by one or more windings 2910, 2915on each side of the transport apparatus 22 that interact with magnets2920 and 2925, respectively, disposed on opposing sides of transportapparatus 22. The windings 2910, 2915 may also provide for closed-loopguidance control and yaw stabilization. Lift, pitch and roll may bestabilized by passive forces. Motion in the z-direction for thisembodiment, if required, may be provided by an external device.

Independent windings 2910, 2915 may be disposed on opposing sides oftransport apparatus 22 and may be embedded in opposing sides oftransport chamber 18, may be exterior to opposing sides of transportchamber 18 or may be disposed on the interior of transport chamber 18.

For passive life, pitch, and roll stabilization, this embodiment mayalso include ferromagnetic components comprising stationaryferromagnetic elements 2935, 2940 and magnets 2920, 2925, respectively,situated proximate each other. Similar to other embodiments, stationaryferromagnetic elements 2935, 2940 may be formed as part of an iron coreor iron backing of the windings 22910, 2915, or may be incorporated aspart of the structure of transport chamber 18. In other embodiments,stationary ferromagnetic elements 2935, 2940 may reside on the exterioror the interior of transport chamber 18.

Similar to the embodiments above, transport apparatus 22 may include oneor more position feedback devices 2945, 2950 and transport chamber 18may include one or more sensors 2955, 2960. Position feedback devices2945, 2950 may be similar to position feedback device 340 (FIG. 10), andsensors 2955, 2960 may be similar to sensor 336 (FIG. 10) describedabove. Control electronics 2715 (FIG. 27) may include connections toposition feedback devices 2945, 2950 and sensors 2955, 2960 and mayutilize signals from the devices and sensors to determine a position oftransport apparatus 22.

Control electronics 2715 (FIG. 27) drive stationary windings 2910, 2915so as to provide closed loop control of the X, y_(F), and y_(R)coordinates of transport apparatus 22, where y_(F) represents theposition of the front 2965 of the transport apparatus 22 and y_(R)represents the position of the rear 2970 of the transport apparatus 22.The combination of magnets 2920, 2925, and stationary ferromagneticelements 2935, 2940 provide passive control of the z, R_(x), and R_(y)position coordinates.

Control electronics 2715 drive stationary windings 2910 2915 in a mannerto apply Lorentz or Maxwell forces on transport apparatus 22, and thecombination of magnets 2920, 2925, and stationary ferromagnetic elements2935, 2940 operate to apply passive forces on transport apparatus 22 asfollows:

-   -   F_(x)=F_(xRF)+F_(xRR), applied as Lorentz forces;    -   F_(yF)=F_(yLF)+F_(yRF), F_(yR)=F_(yLR)+F_(yRR); applied as        Maxwell and/or Lorentz forces; and    -   F_(z), M_(x), M_(y), applied as passive forces.

FIG. 29C illustrates some of the position coordinates and forces appliedto the transport apparatus 22.

Transport apparatus 22 may include two parts, for example, forimplementing movement similar to cart 229 (FIG. 12A) described above.Actuation may be implemented by relative motion of front 2965 and rear2970 sections of transport apparatus 22 with no additional amplifierchannels required.

FIGS. 30-33, 34A, 35A, and 36-38 show exemplary embodiments withmultiple winding sets and amplifier channels. The transport chamber isnot shown for simplicity.

FIG. 30 shows an embodiment that provides closed loop lift, open looppitch and roll stabilization, closed loop propulsion and guidance, andopen loop yaw control.

The embodiment in FIG. 30 includes propulsion windings 3010, 3015positioned on opposing sides of transport apparatus 3005, connectedtogether. In this embodiment, control electronics 2715 (FIG. 27) includeat least two amplifier channels 3020, 3035. Propulsion windings 3010,3015 are driven by a single amplifier channel 3020. Similarly, liftwindings 3025, 3030 are positioned on opposing sides of transportapparatus 22, connected together and driven by a single amplifierchannel 3035.

The propulsion windings 3015 are designed to produce a greater Maxwellforce on the opposing side 3040 of transport apparatus than thepropulsion windings 3010 on side 3045, while lift windings 3025 producea higher Maxwell force on side 3045 than the lift windings 3030 on side3040. A guidance force along the y-axis is produced as a differencebetween the total Maxwell forces produced by the propulsion 3010, 3015and lift 3025, 3030 winding sets. Alternately, the windings may bedesigned and driven to produce Lorentz forces for guidance along they-axis. Both winding sets may be controlled using phase commutation toproduce an open-loop yaw, pitch and roll stabilization effect.

Transport apparatus 3005 includes magnet platens 3050, 3055 on opposingsides 3040, 3045, respectively. Magnet platens 3050, 3055 may bearranged as an array of magnets and may extend along a length of theopposing sides 3040, 3045. In one embodiment, the array of magnets maybe arranged with alternating north poles 3060 and south poles 3065facing the windings. Other magnet arrangements may also be used.

The magnet platens 3050, 3055 and windings 3015, 3030, 3010, 3025 undercontrol of amplifier channels 3020 and 3035 operate to control the x, y,z coordinates of the transport apparatus 3005 using a closed looptechnique, and to control the R_(x), R_(y), R_(z) using an open looptechnique.

The magnet platens 3050, 3055 and windings 3015, 3030, 3010, 3025 undercontrol of amplifier channels 3020 and 3035 interact to apply thefollowing forces to transport apparatus 3005:

-   -   F_(x)=F_(xL)+F_(xR), applied as Lorentz forces;    -   F_(y)=F_(yL)+F_(yR), applied as Maxwell or Lorentz forces,        applied as the difference between guidance forces produced by        propulsion and lift windings on opposing sides;    -   F_(z)=F_(zL)+F_(zR), applied as Lorentz forces; and    -   M_(x), M_(y), M_(z) produced by the open-loop stabilization        effect of phase commutation.

FIG. 31 shows an embodiment of a drive system that provides closed looplift, open loop pitch and roll stabilization, and closed-looppropulsion, guidance and yaw control. In this configuration, propulsionforces are provided by independent propulsion windings 3110, 3115positioned on opposing sides of transport apparatus 3005. While in thisembodiment, control electronics 2715 (FIG. 27) are shown as including asingle channel amplifier 3120 and a two channel amplifier 3125, itshould be understood that any suitable amplifier arrangement thatprovides 3 channels may be used. Propulsion windings 3110, 3115 aredriven by individual channels 3130 and 3135, respectively, of twochannel amplifier 3125. Lift windings 3140, 3145 are connected togetherand driven by single amplifier channel 3120. Lift windings 3140, 3145are controlled using phase commutation so as to achieve open loop pitchand roll stabilization of transport apparatus 3005. Guidance force alongthe y-axis is produced by propulsion windings 3110, 3115 utilizingMaxwell or Lorentz principles.

As described with respect to the embodiment of FIG. 30, transportapparatus 3005 includes magnet platens 3050, 3055. Magnet platens 3050,3055 and windings 3110, 3115, 3140, 3145 under control of amplifierchannels 3120, 3130, and 3135 operate to control the x_(L), x_(R), y, zcoordinates using a closed-loop technique, and to control the R_(x),R_(y) coordinates using an open-loop technique.

The magnet platens 3050, 3055 and windings 3015, 3030, 3010, 3025 undercontrol of amplifier channels 3020 and 3035 operate to apply thefollowing forces to transport apparatus 3005:

-   -   F_(xL), F_(xR), applied as Lorentz forces;    -   F_(y)=F_(yL)+F_(yR), applied as Maxwell or Lorentz forces        produced by propulsion windings 3110, 3115 only;    -   F_(z)=F_(zL)+F_(zR), applied as Lorentz forces; and    -   M_(x), M_(y), produced by open-loop stabilization due to phase        commutation of lift windings 3140, 3145.

FIG. 32 shows an embodiment of a drive system that provides closed looplift, open-loop pitch stabilization, closed loop roll stabilization,propulsion, guidance, and yaw control.

In this configuration, propulsion forces are provided by independentpropulsion windings 3210, 3215 positioned on opposing sides of transportapparatus 3005, while lift is provided by independent lift windings3220, 3225 also positioned on opposing sides of transport apparatus3005. While in this embodiment, control electronics 2715 (FIG. 27) areshown as including two dual channel amplifiers 3230, 3235, it should beunderstood that any suitable amplifier arrangement that provides 4channels may be utilized. Propulsion windings 3210, 3215 are driven byindividual channels 3240 and 3245, respectively, of two channelamplifier 3230. Correspondingly, lift windings 3220, 3225 are driven byindividual channels 3250 and 3255, respectively, of two channelamplifier 3235. Lift windings 3220, 3225 are controlled using phasecommutation so as to achieve open loop pitch stabilization of transportapparatus 3005. Guidance force along the y-axis is produced by bothpropulsion windings 3210, 3215 and lift windings 3220, 3225 utilizingMaxwell principles.

As described with respect to other embodiments above, transportapparatus 3005 includes magnet platens 3050, 3055. Magnet platens 3050,3055 and windings 3210, 3215, 3220, 3225 under control of amplifierchannels 3240, 3245, 3250, 3255, respectively, operate to control thexL, xR, y, zL, zR coordinates using a closed-loop technique and the Rycoordinates using an open-loop technique.

The magnet platens 3050, 3055 and windings 3210, 3215, 3220, 3225 undercontrol of amplifier channels 3240, 3245, 3250, 3255, respectively,operate to apply the following forces to transport apparatus 3005:

-   -   F_(x)=F_(xL)+F_(xR), applied as Lorentz forces;    -   F_(y)=F_(yL)+F_(yR), applied as Maxwell forces, produced by both        propulsion windings 3210, 3215 and lift windings 3220, 3225;    -   F_(z)=F_(zL)+F_(zR), applied as Lorentz forces; and    -   M_(y) produced by open-loop stabilization due to phase        commutation of lift windings 3220, 3225.

FIGS. 33, 34A-34D, and 35 through 38 illustrate embodiments of drivesystems with full closed-loop control, that is, there is no open-loop orpassive control of coordinates or forces. These embodiments operate tolevitate and propel transport apparatus 3305 using stationary windingsthat interact with a number of magnet platens coupled to transportapparatus 3305. While the embodiments show, for example, four magnetplatens 3375, 3380, 3385, and 3390, one coupled to each corner oftransport apparatus 3305, it should be understood that any number ofmagnet platens may be used in any arrangement with respect to transportapparatus 3305. While the embodiments show the magnet platens withmagnets arranged in an alternating north south pole pattern, it shouldalso be understood that any suitable pattern of magnets may be used.

Turning to FIG. 33, propulsion windings 3310 and 3315 on opposing sides3320 and 3325, respectively, of transport apparatus 3305 may beconnected together and driven by single amplifier channel 3330. Threeindependent lift windings 3335, 3340, and 3345 may be driven by threeamplifier channels 3360, 3365, and 3370, respectively. The threeindependent lift windings operate to produce lift forces with a singlewinding 3335 acting on side 3325, and windings 3340, 3345 acting on side3320. In this embodiment, winding 3345 acts on the front 3350 oftransport apparatus 3305 along side 3320, while winding 3340 acts on therear 3355 of transport apparatus 3305 along side 3320. Thus, a commonlift force may be applied to side 3325, while independent lift forces,which may be the same or different, may be applied to the front and rearof side 3320.

Magnet platens 3375, 3380, 3385, 3390 and windings 33310, 3315, 3335,3340, and 3345 under control of amplifier channels 3330, 3360, 3365, and3370, respectively, operate to control the x, yF, yR, zL, zRF, zRR,coordinates using a closed-loop technique.

Magnet platens 3375, 3380, 3385, 3390 and windings 33310, 3315, 3335,3340, and 3345 under control of amplifier channels 3330, 3360, 3365, and3370, respectively, operate to apply the following forces to transportapparatus 3305:

-   -   F_(x)=F_(xL)+F_(xR), applied as Lorentz forces;    -   F_(yF)=F_(yL)/2+F_(yLR), F_(yR)=F_(yL)/2+F_(yRR), applied as        Lorentz or Maxwell force, produced by the lift windings only;        and    -   F_(zL), F_(zRF), F_(zRR), applied as Lorentz forces.

Referring now to FIG. 34A, four independent lift windings 3410, 3415,3420, and 3425 may be driven by four amplifier channels 3430, 3435,3440, and 3445, respectively. The four independent lift windings operateto produce lift forces on magnet platens on each corner of transportapparatus 3305, with windings 3410, 3415, 3420, and 3425 producing liftforces on magnet platens 3450, 3455, 3460, and 3465, respectively. Thus,independent lift forces may be applied to each magnet platen 3450, 3455,3460, and 3465 and therefore to each corner of transport apparatus 3305.

In this embodiment, propulsion windings 3490 and 3495 are connectedtogether and driven by single amplifier channel 3497.

Magnet platens 3450, 3455, 3460, and 3465 and windings 3410, 3415, 3420,3425, 3490 and 3495 under control of amplifier channels 3430, 3435,3440, 3445, and 3497, respectively, operate to control the x, yF, yR,zF, zLR, and zRR, coordinates of transport apparatus 3305 using aclosed-loop technique.

Magnet platens 3450, 3455, 3460, and 3465 and windings 3410, 3415, 3420,3425, 3490 and 3495 under control of amplifier channels 3430, 3435,3440, 3445, and 3497, respectively, operate to apply the followingforces on transport apparatus 3305:

-   -   F_(x)=F_(xL)+F_(xR), applied as Lorentz forces;    -   F_(yF)=F_(yLF)+F_(yRF), F_(yR)=F_(yLR)+F_(yRR), applied as        Lorentz or Maxwell forces, produced by the lift windings only;        and    -   F_(zF)=F_(zLF)+F_(zRF), F_(zLR), F_(zRR) applied as Lorentz        forces.

The drive system of FIG. 34A may also include an array of sensors 3411for determining the location of transport apparatus 3305, which mayinclude the location of certain portions of transport apparatus 3305.For example, sensor array 3411 may be capable of sensing the locationsof each of the magnet platens 3450, 3455, 3460, 3465, thus sensing thelocations of each corner, right front (RF), left front (LF), right rear(RR), and left rear (LR), respectively, of transport apparatus 3305. Inthis embodiment, control electronic 2715 may include sensor circuitry3417 for providing power and for exchanging signals with sensor array3411.

FIGS. 34B-D show exemplary control solutions for lift and guidancecontrol of the front 3403 and rear 3407 of transport apparatus 3305, andfor propulsion control of transport apparatus 3305.

FIG. 34B illustrates an exemplary lift and guidance control solution forthe front end 3403 of transport apparatus 3305. The actual positions ofthe left front LF and right front RF of transport apparatus 3305 alongthe y and z-axes y_(LFact), z_(LFact), y_(RFact), z_(RFact) may beprovided by sensor array 3411. A desired position on the z-axis z_(cmd)may be provided through interface 2735 of control electronics 2715 (FIG.27). The actual positions y_(LFact), z_(LFact), y_(RFact), z_(RFact) anddesired position z_(cmd) may be utilized by amplifier 3419 to producecommutation currents i_(Aj) and i_(Bj) to be provided through amplifierchannels 3430 and 3435 to windings 3410 and 3415, respectively, asillustrated.

FIG. 34C illustrates an exemplary lift and guidance control solution fortransport apparatus 3305 rear end 3407. Sensor array 3411 may providethe actual positions of the left rear LR and right rear RR of transportapparatus 3305 along the y and z-axes y_(LRact), z_(LRact), y_(RRact),z_(RRact). A desired position on the z-axis z_(cmd) may be providedthrough interface 2735 of control electronics 2715 (FIG. 27). The actualpositions y_(LRact), z_(LRaCt), y_(RRact), z_(RRact) and desiredposition z_(cmd) may be utilized by amplifier 3422 to producecommutation currents i_(Aj) and i_(Bj) to be provided through amplifierchannels 3440 and 3445 to windings 3420 and 3425, respectively, asillustrated.

FIG. 34D illustrates an exemplary propulsion control solution fortransport apparatus 3305. The actual position of transport apparatus3305 along the x-axis x_(act) may be provided by sensor array 3411. Adesired position on the x-axis x_(cmd) may be provided through interface2735 of control electronics 2715 (FIG. 27). The actual position x_(act)and desired position x_(cmd) may be utilized by amplifier 3427 toproduce commutation current i_(j) to be provided through amplifierchannel 3497 to windings 3490 and 3495 as illustrated.

FIGS. 35A, 35B, and 36 through 38 depict exemplary drive systemembodiments that provide full closed-loop control and also includeprovisions for actuation of one or more devices on the transportapparatus.

Referring to the embodiment shown in FIG. 35A, four propulsion windingsare provided, 3510 and 3520 on side 3530 of transport apparatus 3505,and 3515 and 3525 on side 3535 of transport apparatus 3505. Propulsionwindings on opposing sides are connected together and driven by a singleamplifier channel, with windings 3510 and 3515 driven by amplifierchannel 3540, and windings 3520 and 3525 driven by amplifier channel3545.

Four independent lift windings 3550, 3555, 3560, and 3565 may be drivenby four amplifier channels 3570, 3575, 3580, and 3585, respectively. Thefour independent lift windings operate to produce independent liftforces, which may be the same or different, on magnet platens on eachcorner of transport apparatus 3505, with windings 3550, 3555, 3560, and3565 producing lift forces on magnet platens 3450, 3455, 3460, and 3465,respectively.

The combination of magnet platens and windings under control of theamplifier channels described in this embodiment operate to control thex, y_(F), y_(R), z_(F), z_(LR), and z_(RR) coordinates of transportapparatus 3505 using closed loop techniques. This combination of magnetplatens and windings under control of the amplifier channels alsooperates to apply the following forces on transport apparatus 3505:

-   -   F_(x)=F_(xLF)+F_(xRF)+F_(xLR)+F_(xRR), applied as Lorentz forces    -   F_(yF)=F_(yLF)+F_(yRF), F_(yR)=F_(yLR)+F_(yRR), applied as        Lorentz or Maxwell forces; that is, if Maxwell principles are        used these forces are produced by the lift windings only, and if        Lorentz principles are used these forces are produced by a        combination of the propulsion and lift windings; and    -   F_(zF)=F_(zLF)+F_(zRF), F_(zLR), F_(zRR), applied as Lorentz        forces.

The drive system of FIG. 35A may also include an array of sensors 3511for determining the location of transport apparatus 3505, which mayinclude the location of certain portions of transport apparatus 3505.For example, sensor array 3511 may be capable of sensing the locationsof each of the magnet platens 3450, 3455, 3460, 3465, thus sensing thelocations of each corner, right front (RF), left front (LF), right rear(RR), and left rear (LR), respectively, of transport apparatus 3505. Inthis embodiment, control electronic 2715 may include sensor circuitry3517 for providing power and for exchanging signals with sensor array3511.

This embodiment may utilize exemplary lift and guidance controlsolutions similar to those shown in FIGS. 34B and 34C.

In this embodiment, transport apparatus 3505 may include two or moreportions, that are movable with respect to each other, similar to theexemplary apparatus shown in FIG. 28D. With a transport apparatus ofthis type, an actuation device on the transport apparatus, for example,an arm or end effector, may be actuated by relative motion of front 3585and rear 3590 sections of transport apparatus 3505 with no additionalamplifier channels required.

FIG. 35B illustrates an exemplary propulsion control solution fortransport apparatus 3505. The actual positions of the front section 3585of transport apparatus 3505 along the x-axis x_(Fact) and the rearsection 3590 of transport apparatus 3505 along the x-axis x_(Ract) maybe provided by sensor array 3411. Desired positions of the front section3585 on the x-axis x_(Fcmd) and the rear section 3590 on the x-axisx_(Rcmd) may be provided through interface 2735 of control electronics2715 (FIG. 27). The actual positions x_(Fact), x_(Ract) and desiredpositions x_(Fcmd), x_(Rcmd) may be utilized by amplifier 3537 toproduce commutation current i_(Aj) to be provided through amplifierchannel 3540 to windings 3510 and 3515. The actual and desired positionsmay also be used to produce commutation current i_(Bj) to be providedthrough amplifier channel 3545 to windings 3520 and 3525 as illustrated.

FIG. 36 shows an embodiment similar to FIG. 35A with the winding setsclustered around the magnet platens 3450, 3455, 3460, 3465.

This embodiment may utilize exemplary lift and guidance controlsolutions similar to those shown in FIGS. 34B and 34C, and may utilizethe exemplary propulsion control solution illustrated in FIG. 35B.

This embodiment is advantageous because it provides the same controlover the coordinates of the transport apparatus 3005 and applies thesame forces as the embodiment illustrated by FIG. 35A without havingareas of the windings that are unused.

The exemplary embodiment shown in FIG. 37 utilizes four independentpropulsion windings and four independent lift windings each driven byits own amplifier channel.

The independent propulsion windings 3710, 3715, 3720, and 3725 may bedriven by four amplifier channels 3730, 3735, 3740, and 3745,respectively. The four independent propulsion windings operate toproduce propulsion forces along the x-axis on magnet platens on eachcorner of transport apparatus 3305, with windings 3710, 3715, 3720, and3725 producing independent propulsion forces, which may be the same ordifferent, on magnet platens 3450, 3455, 3460, and 3465, respectively.

The independent lift windings 3750, 3755, 3760, and 3765 may be drivenby four amplifier channels 3770, 3575, 3780, and 3785, respectively. Thefour independent lift windings operate to produce lift forces on magnetplatens on each corner of transport apparatus 3305, with windings 3750,3755, 3760, and 3765 producing independent lift forces, which may be thesame or different, on magnet platens 3450, 3455, 3460, and 3465,respectively.

Similar to the embodiments of FIGS. 34-36, the combination of magnetplatens and windings under control of the amplifier channels describedin this embodiment operate to control the x, y_(F), y_(R), z_(F),z_(LR), and z_(RR) coordinates of transport apparatus 3305 using closedloop techniques.

This combination of magnet platens and windings under control of theamplifier channels operates to apply the following forces on transportapparatus 3305:

-   -   F_(x)=F_(xLF)+F_(xRF)+F_(xLR)+F_(xRR), applied as Lorentz forces    -   F_(yF)=F_(yLF)+F_(yRF), F_(yR)=F_(yLR)+F_(yRR), applied as        Lorentz or Maxwell forces by a combination of the propulsion and        lift windings; and    -   F_(zF)=F_(zLF)+F_(zRF), F_(zLR), F_(zRR), applied as Lorentz        forces.

In this embodiment, arm actuation may be implemented by relative motionof magnet platens 3450, 3455, 3460, and 3465 of transport apparatus 3305with no additional amplifier channels required.

FIG. 38 shows an embodiment similar to FIG. 37 with the winding setsclustered around the magnet platens 3450, 3455, 3460, 3465.

This embodiment is advantageous because it provides the same controlover the coordinates of the transport apparatus 3005 and applies thesame forces as the embodiment illustrated by FIG. 37 without havingareas of the windings that are unused.

Most of the embodiments disclosed above may utilize relative motion ofthe front and rear portion of transport apparatus 22 for actuating adevice, for example, an arm, end effector, or rotating device, on thetransport apparatus. The relative motion generally results from relativeforces applied to the magnet platens coupled to the front and rearportions of the transport apparatus. As an alternative to relativemotion of the front and rear portions of the transport apparatus, deviceactuation may be achieved by utilizing magnet platens located on thetransport apparatus designated for providing relative movement. Themovement may be caused by interaction between the designated magnetplatens and windings positioned proximate the designated magnet platens.The designated magnet platens may be constructed to be movable relativeto each other in any direction. The designated magnet platens mayinteract with windings specifically designated for providing relativemovement of the designated magnet platens or may interact with windingsalready present for providing forces on the transport apparatus, forexample, lift, propulsion, or guidance, as disclosed herein.

FIGS. 39A-39C show an embodiment including two vertically segmentedmagnet platens, an upper platen 3910 and a lower platen 3915. The upperand lower platens 3910, 3915 may be mounted to a side of any one of thedisclosed transport apparatus, for example transport apparatus 22 or3305. Alternately, the upper and lower platens 3910, 3915 may be mountedto any portion of a transport apparatus. The upper and lower platens3910, 3915 may be mounted on slides or rollers and may be constrainedwithin a set of guides or rails to ensure proper movement.

FIG. 39A shows the upper and lower platens 3910, 3915 situated inneutral positions. As shown in FIG. 39B, lower platen 3915 may be heldstationary while upper platen 3910 may be actuated by forces provided bythe windings. In FIG. 39C upper platen 3910 may be held stationary whilelower platen 3915 may be actuated by forces provided by the windings.

In some embodiments, one of the designated magnet platens may be fixedto the transport apparatus and used for movement of the transportapparatus itself as disclosed, for example, in FIGS. 30-32. In thoseembodiments, the other designated magnet platen may be movably mountedto the transport apparatus for device actuation.

In embodiments where space available along the x-direction may belimited, for example, due to the presence of another transport apparatusin a neighboring station, the designated magnet platens may provide anincreased range of motion of the magnet platens, thus relaxing the forceand position resolution requirements.

FIG. 40 illustrates a drive system in a rotary configuration. In thisembodiment, four independent propulsion windings are driven by fouramplifier channels, respectively, similar to the embodiments of FIGS. 37and 38. The four independent propulsion windings produce fourx-direction forces: F_(xLF), F_(xRF), F_(xLR), F_(xRR).

In this embodiment, transport apparatus 4005 may include a pair ofrotors 4010, 4015 that rotate independently but are coupled together attheir centers. The x-direction forces produce moments that act on thepair of rotors 4010, 4015 for arm actuation purposes, providingadditional two degrees of freedom. In addition, the propulsion windingsare capable of generating guidance forces.

Lift control and pitch/roll stabilization are achieved through liftwindings which may also produce guidance forces. Lift control andpitch/roll stabilization may utilize lift windings similar to any one ofthe embodiments shown in FIGS. 30-38. The transport apparatus 4005 maybe capable of negotiating corners.

The windings interact with the rotors to control the X, y_(F), y_(R),R_(zF), R_(zR) coordinates of transport apparatus 4005 using closed-looptechniques, and to control the z, R_(x), R_(y) coordinates usingclosed-loop, open-loop or a combination depending on the configurationof the lift windings.

The windings also interact with the rotors to apply the following forcesto transport apparatus 4005:

-   -   F_(x)=F_(xLF)+F_(xRF)+F_(xLR)+F_(xRR), applied as Lorentz        forces;    -   F_(yF)=F_(yLF)+F_(yRF), F_(yR)=F_(yLR)+F_(yRR), applied as        Lorentz or Maxwell forces    -   M_(zF)=r(F_(xLF)−F_(xRF)), M_(zR)=r(F_(xLR)−F_(xRR)), r=radius    -   F_(zLF), F_(zRF), F_(zLR), F_(zRR), applied as Lorentz forces.

When utilized in a processing apparatus, for example, those described inFIGS. 2-7, transport apparatus 22, 22A, 3005, 3305, 4005 may be heldstationary while waiting at a station. In some embodiments, this maycause the lift windings to be constantly energized. One or moreembodiments of the drive system may utilize additional ferromagneticelements in order to reduce the continuous force produced by the liftwindings while the transport apparatus is waiting.

The embodiment in FIG. 41 may employ a grid of stationary ferromagneticrails 4105 exposed to the magnetic field of the permanent magnets on thetransport apparatus. As an example, transport apparatus 3305 is shown atthree different locations within the grid 4105. This embodiment may beutilized with any suitable transport apparatus. In this example, thegrid 4105 is exposed to the fields of magnet platens 3450 and 3460.While this embodiment illustrates a single grid, it should be understoodthat any suitable number of grids may be used. In another embodiment twogrids may be located proximate opposing sides of transport apparatus3305 and may interact with magnet platens on the opposing sides oftransport apparatus.

When transport apparatus 3305 holds position, passive forces between themagnet platens 3450, 3460 and the ferromagnetic grid 4105 balance theweight of the transport apparatus 3305. The grid may include a number ofhorizontal rails 4110, 4120 that provide ferromagnetic material along anaxis to allow transport apparatus to traverse a path. In order to allowfor a smooth change across the grid, for example, from one verticallevel to another, additional ferromagnetic rails 4115, 4125 may beprovided. In position A, transport apparatus is shown traversing ahorizontal rail 4120. Position B illustrates how the grid is constructedto allow for transitions between levels. Position C may be an exemplaryholding position where transport apparatus 3305 may wait at a station.

The attractive forces between the magnet platens 3450, 3460 and rails4110, 4115, 4120, 4125 include horizontal components that can be usedfor safe touchdown in power loss situations.

An alternate embodiment may include a magnetic ratcheting mechanism 4205as shown in FIGS. 42A and 42B. In this embodiment, the peak passiveforce Fzup acting on the transport apparatus in the upward direction maybe substantially larger than the passive force produced by the magneticratcheting mechanism in the downward direction Fzdn. Fzdn represents anincremental force increase compared to embodiments without theratcheting mechanism. In other words, the peak force required to movethe cart up from a lower level to a higher level needs to overcomegravity plus Fzdn, and in some embodiments may also include forcerequired to accelerate the cart. The horizontal components of theattractive forces between the magnet platens 3450, 3455 and theferromagnetic elements 4210, 4215 of the ratcheting mechanism canprovide a means of safe touchdown on power loss.

Each of the embodiments disclosed herein may utilize one or morepatterns of stationary windings, examples of which are shown in FIG.43A. The patterns illustrated in FIG. 43A represent differentassemblies, or configurations of windings that may be used, where awinding set may include one pattern or a combination of patterns.

The disclosed embodiments may also include one or more patterns ofmagnet platens, examples of which are illustrated in FIG. 43B. A magnetplaten may include a single pattern or a combination of patterns. InFIG. 43C, Table 1 includes a description of each of the windingpatterns, and Table 2 includes a description of each of the magnetplaten patterns. Table 3 illustrates a number of non-limiting examplesof various combinations of winding patterns and magnet patterns that maybe used together in the drive system embodiments described herein.

Thus, the disclosed embodiments may provide propulsion and lift windingsthat are used for guidance with no need for dedicated guidance windings,in one or more embodiments, a single-sided drive configuration utilizingpassive magnetic forces, passive lift, and pitch and roll stabilizationusing passive magnetic forces. The disclosed embodiments may alsoprovide open-loop lift, pitch and roll stabilization utilizing phasecommutation, drive configurations with vertically segmented magnetplatens for device actuation, and drive configurations for direct rotaryarm actuation, with the capability of negotiating corners. In addition,the embodiments may include passively balanced lift capabilitiesutilizing ferromagnetic rails, passively balanced lift capabilitiesbased on a magnetic ratcheting mechanism, and decoupled closed-loopposition control when, for example, implemented on conventionaldual-channel motor amplifiers.

It should be understood that the foregoing description is onlyillustrative of the disclosed embodiments. Various alternatives andmodifications can be devised by those skilled in the art withoutdeparting from the embodiments disclosed herein. Accordingly, thedisclosed embodiments are intended to embrace all such alternatives,modifications and variances which fall within the scope of the appendedclaims.

What is claimed is:
 1. A drive system for a transport apparatuscomprising: a plurality of permanent magnets connected to the transportapparatus; a plurality of operative and effective stationary windingsexposed to a field of at least one of the plurality of permanentmagnets; a control system for energizing the stationary windings toprovide magnetic force on the transport apparatus; and an arrangement offerromagnetic components proximate at least one side of the transportapparatus for providing passive stabilization of lift, pitch, and rollof the transport apparatus, exclusive of the magnetic force of theoperative and effective stationary windings.
 2. The drive system ofclaim 1, wherein the arrangement of ferromagnetic components comprisesat least another one of the plurality of permanent magnets and one ormore ferromagnetic elements.
 3. The drive system of claim 2, wherein theone or more ferromagnetic elements are formed as part of the pluralityof operative and effective stationary windings.
 4. The drive system ofclaim 1, wherein the operative and effective stationary windings areproximate to one side of the transport apparatus.
 5. The drive system ofclaim 1, wherein the operative and effective stationary windings areproximate to opposing sides of the transport apparatus.
 6. The drivesystem of claim 1, wherein the plurality of permanent magnets comprisesmagnet platens located on first and second opposing sides of thetransport apparatus.
 7. The drive system of claim 6, wherein themagnetic platens include an arrangement of magnets with alternatingpoles facing the windings.
 8. The drive system of claim 6, wherein theoperative and effective stationary windings include: propulsion windingsproximate the first and second opposing sides of the transportapparatus; and lift windings proximate the first and second opposingsides of the transport apparatus.
 9. The drive system of claim 8, wherethe propulsion and lift windings proximate the first opposing side ofthe transport apparatus are offset from respective propulsion and liftwindings proximate the second opposing side of the transport apparatus.10. The drive system of claim 8, wherein the control system comprisescontrol electronics configured for driving the propulsion windings toproduce a propulsion force parallel to the opposing sides of thetransport apparatus, and for driving the lift windings to produce a liftforce perpendicular to the propulsion force.
 11. The drive system ofclaim 10, wherein the control system comprises control electronicsconfigured for driving the propulsion windings to produce a firstguidance force orthogonal to the propulsion and lift forces, and fordriving the lift windings to produce a second guidance force opposingthe first guidance force.
 12. The drive system of claim 10, wherein thecontrol system comprises control electronics configured for driving thepropulsion windings to produce first and second opposing guidance forcesorthogonal to the propulsion and lift forces.
 13. The drive system ofclaim 8, wherein the control system comprises control electronicsconfigured for driving the propulsion and lift windings to producepropulsion and lift forces as Lorentz forces.
 14. The drive system ofclaim 8, wherein the control system comprises control electronicsconfigured for driving the propulsion and lift windings to produceguidance forces as Maxwell forces.
 15. A processing apparatuscomprising: a transport chamber; at least one processing modulecommunicatively coupled to the transport chamber; a transport apparatusfor transporting a workpiece between the transport chamber and the atleast one processing module; a drive system for providing magnetic forcefor moving the transport apparatus through the transport chamber, thedrive system including: a plurality of permanent magnets connected tothe transport apparatus; a plurality of operative and effectivestationary windings exposed to a field of at least one of the pluralityof permanent magnets; a control system for energizing the operative andeffective stationary windings to provide magnetic force on the transportapparatus; and an arrangement of ferromagnetic components proximate atleast one side of the transport apparatus for providing passivestabilization of lift, pitch, and roll of the transport apparatus,exclusive of the magnetic force of the operative and effectivestationary windings.